HADOOP-17271. S3A connector to support IOStatistics. (#2580)

S3A connector to support the IOStatistics API of HADOOP-16830,

This is a major rework of the S3A Statistics collection to

* Embrace the IOStatistics APIs
* Move from direct references of S3AInstrumention statistics
  collectors to interface/implementation classes in new packages.
* Ubiquitous support of IOStatistics, including:
  S3AFileSystem, input and output streams, RemoteIterator instances
  provided in list calls.
* Adoption of new statistic names from hadoop-common

Regarding statistic collection, as well as all existing
statistics, the connector now records min/max/mean durations
of HTTP GET and HEAD requests, and those of LIST operations.

Contributed by Steve Loughran.

Change-Id: I182d34b6ac39e017a8b4a221dad8e930882b39cf

hadoop-tools/hadoop-aws/dev-support/findbugs-exclude.xml

@@ -80,4 +80,14 @@
     <Method name="submit"/>
     <Bug pattern="RV_RETURN_VALUE_IGNORED_BAD_PRACTICE"/>
   </Match>
+  <!--
+  Some of the S3A Instrumentation classes increment volatile references from
+  within synchronized contexts; they use volatile to keep the cost
+  of these updates and reading them down.
+   -->
+  <Match>
+    <Class name="org.apache.hadoop.fs.s3a.S3AInstrumentation$InputStreamStatisticsImpl"/>
+    <Bug pattern="VO_VOLATILE_INCREMENT"/>
+  </Match>
+
 </FindBugsFilter>

hadoop-tools/hadoop-aws/pom.xml

@@ -200,6 +200,8 @@
                     <exclude>**/ITestMarkerToolRootOperations.java</exclude>
                     <!-- operations across the metastore -->
                     <exclude>**/ITestS3GuardDDBRootOperations.java</exclude>
+                    <!-- leave this until the end for better statistics -->
+                    <exclude>**/ITestAggregateIOStatistics.java</exclude>
                   </excludes>
                 </configuration>
               </execution>
@@ -249,6 +251,8 @@
                     <!-- operations across the metastore -->
                     <include>**/ITestS3AContractRootDir.java</include>
                     <include>**/ITestS3GuardDDBRootOperations.java</include>
+                    <!-- leave this until the end for better statistics -->
+                    <include>**/ITestAggregateIOStatistics.java</include>
                   </includes>
                 </configuration>
               </execution>

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/Constants.java

@@ -549,6 +549,13 @@ public final class Constants {
   @InterfaceStability.Unstable
   public static final String INPUT_FADV_RANDOM = "random";
 
+  /**
+   * Gauge name for the input policy : {@value}.
+   * This references an enum currently exclusive to the S3A stream.
+   */
+  public static final String STREAM_READ_GAUGE_INPUT_POLICY =
+      "stream_read_gauge_input_policy";
+
   @InterfaceAudience.Private
   @InterfaceStability.Unstable
   public static final String S3_CLIENT_FACTORY_IMPL =

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/DefaultS3ClientFactory.java

@@ -23,16 +23,26 @@ import java.net.URI;
 
 import com.amazonaws.ClientConfiguration;
 import com.amazonaws.auth.AWSCredentialsProvider;
+import com.amazonaws.client.builder.AwsClientBuilder;
+import com.amazonaws.metrics.RequestMetricCollector;
 import com.amazonaws.services.s3.AmazonS3;
 import com.amazonaws.services.s3.AmazonS3Client;
+import com.amazonaws.services.s3.AmazonS3ClientBuilder;
 import com.amazonaws.services.s3.S3ClientOptions;
+import com.amazonaws.services.s3.internal.ServiceUtils;
+import com.amazonaws.util.AwsHostNameUtils;
+import com.amazonaws.util.RuntimeHttpUtils;
+import org.apache.hadoop.thirdparty.com.google.common.annotations.VisibleForTesting;
 import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import org.apache.commons.lang3.StringUtils;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.conf.Configured;
+import org.apache.hadoop.fs.s3a.statistics.StatisticsFromAwsSdk;
+import org.apache.hadoop.fs.s3a.statistics.impl.AwsStatisticsCollector;
 
 import static org.apache.hadoop.fs.s3a.Constants.EXPERIMENTAL_AWS_INTERNAL_THROTTLING;
 import static org.apache.hadoop.fs.s3a.Constants.ENDPOINT;
@@ -41,7 +51,7 @@ import static org.apache.hadoop.fs.s3a.Constants.PATH_STYLE_ACCESS;
 
 /**
  * The default {@link S3ClientFactory} implementation.
- * This which calls the AWS SDK to configure and create an
+ * This calls the AWS SDK to configure and create an
  * {@link AmazonS3Client} that communicates with the S3 service.
  */
 @InterfaceAudience.Private
@@ -49,13 +59,30 @@ import static org.apache.hadoop.fs.s3a.Constants.PATH_STYLE_ACCESS;
 public class DefaultS3ClientFactory extends Configured
     implements S3ClientFactory {
 
-  protected static final Logger LOG = S3AFileSystem.LOG;
+  private static final String S3_SERVICE_NAME = "s3";
+  private static final String S3_SIGNER = "S3SignerType";
+  private static final String S3_V4_SIGNER = "AWSS3V4SignerType";
 
+  /**
+   * Subclasses refer to this.
+   */
+  protected static final Logger LOG =
+      LoggerFactory.getLogger(DefaultS3ClientFactory.class);
+
+  /**
+   * Create the client.
+   * <p>
+   * If the AWS stats are not null then a {@link AwsStatisticsCollector}.
+   * is created to bind to the two.
+   * <i>Important: until this binding works properly across regions,
+   * this should be null.</i>
+   */
   @Override
   public AmazonS3 createS3Client(URI name,
       final String bucket,
       final AWSCredentialsProvider credentials,
-      final String userAgentSuffix) throws IOException {
+      final String userAgentSuffix,
+      final StatisticsFromAwsSdk statisticsFromAwsSdk) throws IOException {
     Configuration conf = getConf();
     final ClientConfiguration awsConf = S3AUtils
         .createAwsConf(conf, bucket, Constants.AWS_SERVICE_IDENTIFIER_S3);
@@ -72,36 +99,124 @@ public class DefaultS3ClientFactory extends Configured
     if (!StringUtils.isEmpty(userAgentSuffix)) {
       awsConf.setUserAgentSuffix(userAgentSuffix);
     }
-    return configureAmazonS3Client(
-        newAmazonS3Client(credentials, awsConf), conf);
+    // optional metrics
+    RequestMetricCollector metrics = statisticsFromAwsSdk != null
+        ? new AwsStatisticsCollector(statisticsFromAwsSdk)
+        : null;
+
+    return newAmazonS3Client(
+        credentials,
+        awsConf,
+        metrics,
+        conf.getTrimmed(ENDPOINT, ""),
+        conf.getBoolean(PATH_STYLE_ACCESS, false));
   }
 
   /**
-   * Wrapper around constructor for {@link AmazonS3} client.
+   * Create an {@link AmazonS3} client.
    * Override this to provide an extended version of the client
    * @param credentials credentials to use
    * @param awsConf  AWS configuration
-   * @return  new AmazonS3 client
+   * @param metrics metrics collector or null
+   * @param endpoint endpoint string; may be ""
+   * @param pathStyleAccess enable path style access?
+   * @return new AmazonS3 client
    */
   protected AmazonS3 newAmazonS3Client(
-      AWSCredentialsProvider credentials, ClientConfiguration awsConf) {
-    return new AmazonS3Client(credentials, awsConf);
+      final AWSCredentialsProvider credentials,
+      final ClientConfiguration awsConf,
+      final RequestMetricCollector metrics,
+      final String endpoint,
+      final boolean pathStyleAccess) {
+    if (metrics != null) {
+      LOG.debug("Building S3 client using the SDK builder API");
+      return buildAmazonS3Client(credentials, awsConf, metrics, endpoint,
+          pathStyleAccess);
+    } else {
+      LOG.debug("Building S3 client using the SDK builder API");
+      return classicAmazonS3Client(credentials, awsConf, endpoint,
+          pathStyleAccess);
+    }
   }
 
   /**
-   * Configure S3 client from the Hadoop configuration.
-   *
+   * Use the (newer) Builder SDK to create a an AWS S3 client.
+   * <p>
+   * This has a more complex endpoint configuration in a
+   * way which does not yet work in this code in a way
+   * which doesn't trigger regressions. So it is only used
+   * when SDK metrics are supplied.
+   * @param credentials credentials to use
+   * @param awsConf  AWS configuration
+   * @param metrics metrics collector or null
+   * @param endpoint endpoint string; may be ""
+   * @param pathStyleAccess enable path style access?
+   * @return new AmazonS3 client
+   */
+  private AmazonS3 buildAmazonS3Client(
+      final AWSCredentialsProvider credentials,
+      final ClientConfiguration awsConf,
+      final RequestMetricCollector metrics,
+      final String endpoint,
+      final boolean pathStyleAccess) {
+    AmazonS3ClientBuilder b = AmazonS3Client.builder();
+    b.withCredentials(credentials);
+    b.withClientConfiguration(awsConf);
+    b.withPathStyleAccessEnabled(pathStyleAccess);
+    if (metrics != null) {
+      b.withMetricsCollector(metrics);
+    }
+
+    // endpoint set up is a PITA
+    //  client.setEndpoint("") is no longer available
+    AwsClientBuilder.EndpointConfiguration epr
+        = createEndpointConfiguration(endpoint, awsConf);
+    if (epr != null) {
+      // an endpoint binding was constructed: use it.
+      b.withEndpointConfiguration(epr);
+    }
+    final AmazonS3 client = b.build();
+    return client;
+  }
+
+  /**
+   * Wrapper around constructor for {@link AmazonS3} client.
+   * Override this to provide an extended version of the client.
+   * <p>
+   * This uses a deprecated constructor -it is currently
+   * the only one which works for us.
+   * @param credentials credentials to use
+   * @param awsConf  AWS configuration
+   * @param endpoint endpoint string; may be ""
+   * @param pathStyleAccess enable path style access?
+   * @return new AmazonS3 client
+   */
+  @SuppressWarnings("deprecation")
+  private AmazonS3 classicAmazonS3Client(
+      AWSCredentialsProvider credentials,
+      ClientConfiguration awsConf,
+      final String endpoint,
+      final boolean pathStyleAccess) {
+    final AmazonS3 client = new AmazonS3Client(credentials, awsConf);
+    return configureAmazonS3Client(client, endpoint, pathStyleAccess);
+  }
+
+  /**
+   * Configure classic S3 client.
+   * <p>
    * This includes: endpoint, Path Access and possibly other
    * options.
    *
-   * @param conf Hadoop configuration
+   * @param s3 S3 Client.
+   * @param endPoint s3 endpoint, may be empty
+   * @param pathStyleAccess enable path style access?
    * @return S3 client
    * @throws IllegalArgumentException if misconfigured
    */
-  private static AmazonS3 configureAmazonS3Client(AmazonS3 s3,
-      Configuration conf)
+  protected static AmazonS3 configureAmazonS3Client(AmazonS3 s3,
+      final String endPoint,
+      final boolean pathStyleAccess)
       throws IllegalArgumentException {
-    String endPoint = conf.getTrimmed(ENDPOINT, "");
     if (!endPoint.isEmpty()) {
       try {
         s3.setEndpoint(endPoint);
@@ -111,7 +226,7 @@ public class DefaultS3ClientFactory extends Configured
         throw new IllegalArgumentException(msg, e);
       }
     }
-    return applyS3ClientOptions(s3, conf);
+    return applyS3ClientOptions(s3, pathStyleAccess);
   }
 
   /**
@@ -119,23 +234,23 @@ public class DefaultS3ClientFactory extends Configured
    * the Hadoop configuration.
    * This is different from the general AWS configuration creation as
    * it is unique to S3 connections.
-   *
+   * <p>
    * The {@link Constants#PATH_STYLE_ACCESS} option enables path-style access
    * to S3 buckets if configured.  By default, the
    * behavior is to use virtual hosted-style access with URIs of the form
    * {@code http://bucketname.s3.amazonaws.com}
+   * <p>
    * Enabling path-style access and a
    * region-specific endpoint switches the behavior to use URIs of the form
    * {@code http://s3-eu-west-1.amazonaws.com/bucketname}.
    * It is common to use this when connecting to private S3 servers, as it
    * avoids the need to play with DNS entries.
    * @param s3 S3 client
-   * @param conf Hadoop configuration
+   * @param pathStyleAccess enable path style access?
    * @return the S3 client
    */
-  private static AmazonS3 applyS3ClientOptions(AmazonS3 s3,
-      Configuration conf) {
-    final boolean pathStyleAccess = conf.getBoolean(PATH_STYLE_ACCESS, false);
+  protected static AmazonS3 applyS3ClientOptions(AmazonS3 s3,
+      final boolean pathStyleAccess) {
     if (pathStyleAccess) {
       LOG.debug("Enabling path style access!");
       s3.setS3ClientOptions(S3ClientOptions.builder()
@@ -144,4 +259,54 @@ public class DefaultS3ClientFactory extends Configured
     }
     return s3;
   }
+
+  /**
+   * Given an endpoint string, return an endpoint config, or null, if none
+   * is needed.
+   * <p>
+   * This is a pretty painful piece of code. It is trying to replicate
+   * what AwsClient.setEndpoint() does, because you can't
+   * call that setter on an AwsClient constructed via
+   * the builder, and you can't pass a metrics collector
+   * down except through the builder.
+   * <p>
+   * Note also that AWS signing is a mystery which nobody fully
+   * understands, especially given all problems surface in a
+   * "400 bad request" response, which, like all security systems,
+   * provides minimal diagnostics out of fear of leaking
+   * secrets.
+   *
+   * @param endpoint possibly null endpoint.
+   * @param awsConf config to build the URI from.
+   * @return a configuration for the S3 client builder.
+   */
+  @VisibleForTesting
+  public static AwsClientBuilder.EndpointConfiguration
+      createEndpointConfiguration(
+          final String endpoint, final ClientConfiguration awsConf) {
+    LOG.debug("Creating endpoint configuration for {}", endpoint);
+    if (endpoint == null || endpoint.isEmpty()) {
+      // the default endpoint...we should be using null at this point.
+      LOG.debug("Using default endpoint -no need to generate a configuration");
+      return null;
+    }
+
+    final URI epr = RuntimeHttpUtils.toUri(endpoint, awsConf);
+    LOG.debug("Endpoint URI = {}", epr);
+
+    String region;
+    if (!ServiceUtils.isS3USStandardEndpoint(endpoint)) {
+      LOG.debug("Endpoint {} is not the default; parsing", epr);
+      region = AwsHostNameUtils.parseRegion(
+          epr.getHost(),
+          S3_SERVICE_NAME);
+    } else {
+      // US-east, set region == null.
+      LOG.debug("Endpoint {} is the standard one; declare region as null", epr);
+      region = null;
+    }
+    LOG.debug("Region for endpoint {}, URI {} is determined as {}",
+        endpoint, epr, region);
+    return new AwsClientBuilder.EndpointConfiguration(endpoint, region);
+  }
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/InconsistentS3ClientFactory.java

@@ -20,6 +20,7 @@ package org.apache.hadoop.fs.s3a;
 
 import com.amazonaws.ClientConfiguration;
 import com.amazonaws.auth.AWSCredentialsProvider;
+import com.amazonaws.metrics.RequestMetricCollector;
 import com.amazonaws.services.s3.AmazonS3;
 
 import org.apache.hadoop.classification.InterfaceAudience;
@@ -40,12 +41,21 @@ public class InconsistentS3ClientFactory extends DefaultS3ClientFactory {
    * Logs a warning that this is being done.
    * @param credentials credentials to use
    * @param awsConf  AWS configuration
+   * @param metrics metric collector
+   * @param endpoint AWS endpoint
+   * @param pathStyleAccess should path style access be supported?
    * @return an inconsistent client.
    */
   @Override
   protected AmazonS3 newAmazonS3Client(AWSCredentialsProvider credentials,
-      ClientConfiguration awsConf) {
+      ClientConfiguration awsConf,
+      final RequestMetricCollector metrics,
+      final String endpoint,
+      final boolean pathStyleAccess) {
     LOG.warn("** FAILURE INJECTION ENABLED.  Do not run in production! **");
-    return new InconsistentAmazonS3Client(credentials, awsConf, getConf());
+    InconsistentAmazonS3Client s3
+        = new InconsistentAmazonS3Client(credentials, awsConf, getConf());
+    configureAmazonS3Client(s3, endpoint, pathStyleAccess);
+    return s3;
   }
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/Invoker.java

@@ -30,17 +30,19 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import org.apache.commons.lang3.StringUtils;
+import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.io.retry.RetryPolicy;
 import org.apache.hadoop.util.DurationInfo;
+import org.apache.hadoop.util.functional.CallableRaisingIOE;
 
 /**
  * Class to provide lambda expression invocation of AWS operations.
  *
  * The core retry logic is in
- * {@link #retryUntranslated(String, boolean, Retried, Operation)};
+ * {@link #retryUntranslated(String, boolean, Retried, CallableRaisingIOE)};
  * the other {@code retry() and retryUntranslated()} calls are wrappers.
  *
- * The static {@link #once(String, String, Operation)} and
+ * The static {@link #once(String, String, CallableRaisingIOE)} and
  * {@link #once(String, String, VoidOperation)} calls take an operation and
  * return it with AWS exceptions translated to IOEs of some form.
  *
@@ -56,11 +58,13 @@ import org.apache.hadoop.util.DurationInfo;
  * These callbacks can be used for reporting and incrementing statistics.
  *
  * The static {@link #quietly(String, String, VoidOperation)} and
- * {@link #quietlyEval(String, String, Operation)} calls exist to take any
- * operation and quietly catch and log at debug. The return value of
- * {@link #quietlyEval(String, String, Operation)} is a java 8 optional,
+ * {@link #quietlyEval(String, String, CallableRaisingIOE)} calls exist to
+ * take any operation and quietly catch and log at debug.
+ * The return value of {@link #quietlyEval(String, String, CallableRaisingIOE)}
+ * is a java 8 optional,
  * which can then be used in java8-expressions.
  */
+@InterfaceAudience.Private
 public class Invoker {
   private static final Logger LOG = LoggerFactory.getLogger(Invoker.class);
 
@@ -104,10 +108,11 @@ public class Invoker {
    * @throws IOException any IOE raised, or translated exception
    */
   @Retries.OnceTranslated
-  public static <T> T once(String action, String path, Operation<T> operation)
+  public static <T> T once(String action, String path,
+      CallableRaisingIOE<T> operation)
       throws IOException {
     try (DurationInfo ignored = new DurationInfo(LOG, false, "%s", action)) {
-      return operation.execute();
+      return operation.apply();
     } catch (AmazonClientException e) {
       throw S3AUtils.translateException(action, path, e);
     }
@@ -143,7 +148,7 @@ public class Invoker {
       Logger log,
       String action,
       String path,
-      Operation<T> operation) {
+      CallableRaisingIOE<T> operation) {
     try {
       once(action, path, operation);
     } catch (IOException e) {
@@ -280,7 +285,7 @@ public class Invoker {
   public <T> T retry(String action,
       @Nullable String path,
       boolean idempotent,
-      Operation<T> operation)
+      CallableRaisingIOE<T> operation)
       throws IOException {
 
     return retry(action, path, idempotent, retryCallback, operation);
@@ -288,7 +293,7 @@ public class Invoker {
 
   /**
    * Execute a function with retry processing.
-   * Uses {@link #once(String, String, Operation)} as the inner
+   * Uses {@link #once(String, String, CallableRaisingIOE)} as the inner
    * invocation mechanism before retry logic is performed.
    * @param <T> type of return value
    * @param action action to execute (used in error messages)
@@ -306,7 +311,7 @@ public class Invoker {
       @Nullable String path,
       boolean idempotent,
       Retried retrying,
-      Operation<T> operation)
+      CallableRaisingIOE<T> operation)
       throws IOException {
     return retryUntranslated(
         toDescription(action, path),
@@ -317,7 +322,7 @@ public class Invoker {
 
   /**
    * Execute a function with retry processing when doRetry=true, else just once.
-   * Uses {@link #once(String, String, Operation)} as the inner
+   * Uses {@link #once(String, String, CallableRaisingIOE)} as the inner
    * invocation mechanism before retry logic is performed.
    * @param <T> type of return value
    * @param doRetry true if retries should be performed
@@ -337,7 +342,7 @@ public class Invoker {
       @Nullable String path,
       boolean idempotent,
       Retried retrying,
-      Operation<T> operation)
+      CallableRaisingIOE<T> operation)
       throws IOException {
     if (doRetry) {
       return retryUntranslated(
@@ -366,7 +371,7 @@ public class Invoker {
   public <T> T retryUntranslated(
       String text,
       boolean idempotent,
-      Operation<T> operation) throws IOException {
+      CallableRaisingIOE<T> operation) throws IOException {
     return retryUntranslated(text, idempotent,
         retryCallback, operation);
   }
@@ -391,7 +396,7 @@ public class Invoker {
       String text,
       boolean idempotent,
       Retried retrying,
-      Operation<T> operation) throws IOException {
+      CallableRaisingIOE<T> operation) throws IOException {
 
     Preconditions.checkArgument(retrying != null, "null retrying argument");
     int retryCount = 0;
@@ -404,7 +409,7 @@ public class Invoker {
           LOG.debug("retry #{}", retryCount);
         }
         // execute the operation, returning if successful
-        return operation.execute();
+        return operation.apply();
       } catch (IOException | SdkBaseException e) {
         caught = e;
       }
@@ -490,7 +495,7 @@ public class Invoker {
    */
   public static <T> Optional<T> quietlyEval(String action,
       String path,
-      Operation<T> operation) {
+      CallableRaisingIOE<T> operation) {
     try {
       return Optional.of(once(action, path, operation));
     } catch (Exception e) {
@@ -510,15 +515,6 @@ public class Invoker {
         (StringUtils.isNotEmpty(path) ? (" on " + path) : "");
   }
 
-  /**
-   * Arbitrary operation throwing an IOException.
-   * @param <T> return type
-   */
-  @FunctionalInterface
-  public interface Operation<T> {
-    T execute() throws IOException;
-  }
-
   /**
    * Void operation which may raise an IOException.
    */

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/Listing.java

@@ -38,8 +38,11 @@ import org.apache.hadoop.fs.s3a.s3guard.DirListingMetadata;
 import org.apache.hadoop.fs.s3a.s3guard.MetadataStoreListFilesIterator;
 import org.apache.hadoop.fs.s3a.s3guard.PathMetadata;
 import org.apache.hadoop.fs.s3a.s3guard.S3Guard;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
+import org.apache.hadoop.fs.statistics.impl.IOStatisticsStore;
+import org.apache.hadoop.util.functional.RemoteIterators;
 
-import org.apache.hadoop.thirdparty.com.google.common.base.Preconditions;
 import org.slf4j.Logger;
 
 import java.io.FileNotFoundException;
@@ -48,7 +51,6 @@ import java.time.Instant;
 import java.time.OffsetDateTime;
 import java.time.ZoneOffset;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
@@ -57,6 +59,7 @@ import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Set;
 import java.util.concurrent.CompletableFuture;
+import java.util.StringJoiner;
 
 import static org.apache.hadoop.fs.impl.FutureIOSupport.awaitFuture;
 import static org.apache.hadoop.fs.s3a.Constants.S3N_FOLDER_SUFFIX;
@@ -67,6 +70,12 @@ import static org.apache.hadoop.fs.s3a.S3AUtils.objectRepresentsDirectory;
 import static org.apache.hadoop.fs.s3a.S3AUtils.stringify;
 import static org.apache.hadoop.fs.s3a.S3AUtils.translateException;
 import static org.apache.hadoop.fs.s3a.auth.RoleModel.pathToKey;
+import static org.apache.hadoop.fs.statistics.StoreStatisticNames.OBJECT_CONTINUE_LIST_REQUEST;
+import static org.apache.hadoop.fs.statistics.StoreStatisticNames.OBJECT_LIST_REQUEST;
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.iostatisticsStore;
+import static org.apache.hadoop.util.functional.RemoteIterators.filteringRemoteIterator;
+import static org.apache.hadoop.util.functional.RemoteIterators.remoteIteratorFromArray;
+import static org.apache.hadoop.util.functional.RemoteIterators.remoteIteratorFromSingleton;
 
 /**
  * Place for the S3A listing classes; keeps all the small classes under control.
@@ -96,11 +105,14 @@ public class Listing extends AbstractStoreOperation {
    * @param acceptor the file status acceptor
    * @return the file status iterator
    */
-  ProvidedFileStatusIterator createProvidedFileStatusIterator(
+  RemoteIterator<S3AFileStatus> createProvidedFileStatusIterator(
       S3AFileStatus[] fileStatuses,
       PathFilter filter,
       FileStatusAcceptor acceptor) {
-    return new ProvidedFileStatusIterator(fileStatuses, filter, acceptor);
+    return filteringRemoteIterator(
+        remoteIteratorFromArray(fileStatuses),
+        status ->
+            filter.accept(status.getPath()) && acceptor.accept(status));
   }
 
   /**
@@ -109,11 +121,11 @@ public class Listing extends AbstractStoreOperation {
    * @return the file status iterator.
    */
   @VisibleForTesting
-  public static ProvidedFileStatusIterator toProvidedFileStatusIterator(
+  public static RemoteIterator<S3AFileStatus> toProvidedFileStatusIterator(
           S3AFileStatus[] fileStatuses) {
-    return new ProvidedFileStatusIterator(fileStatuses,
-            ACCEPT_ALL,
-            Listing.ACCEPT_ALL_BUT_S3N);
+    return filteringRemoteIterator(
+        remoteIteratorFromArray(fileStatuses),
+        Listing.ACCEPT_ALL_BUT_S3N::accept);
   }
 
   /**
@@ -185,9 +197,11 @@ public class Listing extends AbstractStoreOperation {
    * @return a new remote iterator
    */
   @VisibleForTesting
-  public LocatedFileStatusIterator createLocatedFileStatusIterator(
+  public RemoteIterator<S3ALocatedFileStatus> createLocatedFileStatusIterator(
       RemoteIterator<S3AFileStatus> statusIterator) {
-    return new LocatedFileStatusIterator(statusIterator);
+    return RemoteIterators.mappingRemoteIterator(
+        statusIterator,
+        listingOperationCallbacks::toLocatedFileStatus);
   }
 
   /**
@@ -199,11 +213,28 @@ public class Listing extends AbstractStoreOperation {
    * @return a new remote iterator.
    */
   @VisibleForTesting
-  TombstoneReconcilingIterator createTombstoneReconcilingIterator(
-      RemoteIterator<S3ALocatedFileStatus> iterator, Set<Path> tombstones) {
-    return new TombstoneReconcilingIterator(iterator, tombstones);
+  RemoteIterator<S3ALocatedFileStatus> createTombstoneReconcilingIterator(
+      RemoteIterator<S3ALocatedFileStatus> iterator,
+      @Nullable Set<Path> tombstones) {
+    if (tombstones == null || tombstones.isEmpty()) {
+      // no need to filter.
+      return iterator;
+    } else {
+      return filteringRemoteIterator(
+          iterator,
+          candidate -> !tombstones.contains(candidate.getPath()));
+    }
   }
 
+  /**
+   * Create a remote iterator from a single status entry.
+   * @param status status
+   * @return iterator.
+   */
+  public RemoteIterator<S3ALocatedFileStatus> createSingleStatusIterator(
+      S3ALocatedFileStatus status) {
+    return remoteIteratorFromSingleton(status);
+  }
 
   /**
    * List files under a path assuming the path to be a directory.
@@ -369,7 +400,7 @@ public class Listing extends AbstractStoreOperation {
                     allowAuthoritative);
     // In auth mode return directly with auth flag.
     if (allowAuthoritative && dirMeta != null && dirMeta.isAuthoritative()) {
-      ProvidedFileStatusIterator mfsItr = createProvidedFileStatusIterator(
+      RemoteIterator<S3AFileStatus> mfsItr = createProvidedFileStatusIterator(
               S3Guard.dirMetaToStatuses(dirMeta),
               ACCEPT_ALL,
               Listing.ACCEPT_ALL_BUT_S3N);
@@ -429,105 +460,6 @@ public class Listing extends AbstractStoreOperation {
     boolean accept(FileStatus status);
   }
 
-  /**
-   * A remote iterator which only iterates over a single `LocatedFileStatus`
-   * value.
-   *
-   * If the status value is null, the iterator declares that it has no data.
-   * This iterator is used to handle {@link S3AFileSystem#listStatus(Path)}
-   * calls where the path handed in refers to a file, not a directory:
-   * this is the iterator returned.
-   */
-  static final class SingleStatusRemoteIterator
-      implements RemoteIterator<S3ALocatedFileStatus> {
-
-    /**
-     * The status to return; set to null after the first iteration.
-     */
-    private S3ALocatedFileStatus status;
-
-    /**
-     * Constructor.
-     * @param status status value: may be null, in which case
-     * the iterator is empty.
-     */
-    SingleStatusRemoteIterator(S3ALocatedFileStatus status) {
-      this.status = status;
-    }
-
-    /**
-     * {@inheritDoc}
-     * @return true if there is a file status to return: this is always false
-     * for the second iteration, and may be false for the first.
-     * @throws IOException never
-     */
-    @Override
-    public boolean hasNext() throws IOException {
-      return status != null;
-    }
-
-    /**
-     * {@inheritDoc}
-     * @return the non-null status element passed in when the instance was
-     * constructed, if it ha not already been retrieved.
-     * @throws IOException never
-     * @throws NoSuchElementException if this is the second call, or it is
-     * the first call and a null {@link LocatedFileStatus} entry was passed
-     * to the constructor.
-     */
-    @Override
-    public S3ALocatedFileStatus next() throws IOException {
-      if (hasNext()) {
-        S3ALocatedFileStatus s = this.status;
-        status = null;
-        return s;
-      } else {
-        throw new NoSuchElementException();
-      }
-    }
-  }
-
-  /**
-   * This wraps up a provided non-null list of file status as a remote iterator.
-   *
-   * It firstly filters the provided list and later {@link #next} call will get
-   * from the filtered list. This suffers from scalability issues if the
-   * provided list is too large.
-   *
-   * There is no remote data to fetch.
-   */
-  static class ProvidedFileStatusIterator
-      implements RemoteIterator<S3AFileStatus> {
-    private final ArrayList<S3AFileStatus> filteredStatusList;
-    private int index = 0;
-
-    ProvidedFileStatusIterator(S3AFileStatus[] fileStatuses, PathFilter filter,
-        FileStatusAcceptor acceptor) {
-      Preconditions.checkArgument(fileStatuses != null, "Null status list!");
-
-      filteredStatusList = new ArrayList<>(fileStatuses.length);
-      for (S3AFileStatus status : fileStatuses) {
-        if (filter.accept(status.getPath()) && acceptor.accept(status)) {
-          filteredStatusList.add(status);
-        }
-      }
-      filteredStatusList.trimToSize();
-    }
-
-    @Override
-    public boolean hasNext() throws IOException {
-      return index < filteredStatusList.size();
-    }
-
-    @Override
-    public S3AFileStatus next() throws IOException {
-      if (!hasNext()) {
-        throw new NoSuchElementException();
-      }
-      return filteredStatusList.get(index++);
-    }
-  }
-
   /**
    * Wraps up object listing into a remote iterator which will ask for more
    * listing data if needed.
@@ -555,7 +487,7 @@ public class Listing extends AbstractStoreOperation {
    * Thread safety: None.
    */
   class FileStatusListingIterator
-      implements RemoteIterator<S3AFileStatus> {
+      implements RemoteIterator<S3AFileStatus>, IOStatisticsSource {
 
     /** Source of objects. */
     private final ObjectListingIterator source;
@@ -758,6 +690,23 @@ public class Listing extends AbstractStoreOperation {
     public int getBatchSize() {
       return batchSize;
     }
+
+    /**
+     * Return any IOStatistics provided by the underlying stream.
+     * @return IO stats from the inner stream.
+     */
+    @Override
+    public IOStatistics getIOStatistics() {
+      return source.getIOStatistics();
+    }
+
+    @Override
+    public String toString() {
+      return new StringJoiner(", ",
+          FileStatusListingIterator.class.getSimpleName() + "[", "]")
+          .add(source.toString())
+          .toString();
+    }
   }
 
   /**
@@ -780,7 +729,8 @@ public class Listing extends AbstractStoreOperation {
    *
    * Thread safety: none.
    */
-  class ObjectListingIterator implements RemoteIterator<S3ListResult> {
+  class ObjectListingIterator implements RemoteIterator<S3ListResult>,
+      IOStatisticsSource {
 
     /** The path listed. */
     private final Path listPath;
@@ -805,6 +755,8 @@ public class Listing extends AbstractStoreOperation {
      */
     private int maxKeys;
 
+    private final IOStatisticsStore iostats;
+
     /**
      * Future to store current batch listing result.
      */
@@ -828,10 +780,14 @@ public class Listing extends AbstractStoreOperation {
         S3ListRequest request) throws IOException {
       this.listPath = listPath;
       this.maxKeys = listingOperationCallbacks.getMaxKeys();
-      this.s3ListResultFuture = listingOperationCallbacks
-              .listObjectsAsync(request);
       this.request = request;
       this.objectsPrev = null;
+      this.iostats = iostatisticsStore()
+          .withDurationTracking(OBJECT_LIST_REQUEST)
+          .withDurationTracking(OBJECT_CONTINUE_LIST_REQUEST)
+          .build();
+      this.s3ListResultFuture = listingOperationCallbacks
+          .listObjectsAsync(request, iostats);
     }
 
     /**
@@ -895,7 +851,7 @@ public class Listing extends AbstractStoreOperation {
         LOG.debug("[{}], Requesting next {} objects under {}",
                 listingCount, maxKeys, listPath);
         s3ListResultFuture = listingOperationCallbacks
-                .continueListObjectsAsync(request, objects);
+                .continueListObjectsAsync(request, objects, iostats);
       }
     }
 
@@ -903,7 +859,13 @@ public class Listing extends AbstractStoreOperation {
     public String toString() {
       return "Object listing iterator against " + listPath
           + "; listing count "+ listingCount
-          + "; isTruncated=" + objects.isTruncated();
+          + "; isTruncated=" + objects.isTruncated()
+          + "; " + iostats;
+    }
+
+    @Override
+    public IOStatistics getIOStatistics() {
+      return iostats;
     }
 
     /**
@@ -966,89 +928,6 @@ public class Listing extends AbstractStoreOperation {
     }
   }
 
-  /**
-   * Take a remote iterator over a set of {@link FileStatus} instances and
-   * return a remote iterator of {@link LocatedFileStatus} instances.
-   */
-  class LocatedFileStatusIterator
-      implements RemoteIterator<S3ALocatedFileStatus> {
-    private final RemoteIterator<S3AFileStatus> statusIterator;
-
-    /**
-     * Constructor.
-     * @param statusIterator an iterator over the remote status entries
-     */
-    LocatedFileStatusIterator(RemoteIterator<S3AFileStatus> statusIterator) {
-      this.statusIterator = statusIterator;
-    }
-
-    @Override
-    public boolean hasNext() throws IOException {
-      return statusIterator.hasNext();
-    }
-
-    @Override
-    public S3ALocatedFileStatus next() throws IOException {
-      return listingOperationCallbacks
-              .toLocatedFileStatus(statusIterator.next());
-    }
-  }
-
-  /**
-   * Wraps another iterator and filters out files that appear in the provided
-   * set of tombstones.  Will read ahead in the iterator when necessary to
-   * ensure that emptiness is detected early enough if only deleted objects
-   * remain in the source iterator.
-   */
-  static class TombstoneReconcilingIterator implements
-      RemoteIterator<S3ALocatedFileStatus> {
-    private S3ALocatedFileStatus next = null;
-    private final RemoteIterator<S3ALocatedFileStatus> iterator;
-    private final Set<Path> tombstones;
-
-    /**
-     * @param iterator Source iterator to filter
-     * @param tombstones set of tombstone markers to filter out of results
-     */
-    TombstoneReconcilingIterator(RemoteIterator<S3ALocatedFileStatus>
-        iterator, Set<Path> tombstones) {
-      this.iterator = iterator;
-      if (tombstones != null) {
-        this.tombstones = tombstones;
-      } else {
-        this.tombstones = Collections.emptySet();
-      }
-    }
-
-    private boolean fetch() throws IOException {
-      while (next == null && iterator.hasNext()) {
-        S3ALocatedFileStatus candidate = iterator.next();
-        if (!tombstones.contains(candidate.getPath())) {
-          next = candidate;
-          return true;
-        }
-      }
-      return false;
-    }
-
-    public boolean hasNext() throws IOException {
-      if (next != null) {
-        return true;
-      }
-      return fetch();
-    }
-
-    public S3ALocatedFileStatus next() throws IOException {
-      if (hasNext()) {
-        S3ALocatedFileStatus result = next;
-        next = null;
-        fetch();
-        return result;
-      }
-      throw new NoSuchElementException();
-    }
-  }
-
   /**
    * Accept all entries except those which map to S3N pseudo directory markers.
    */
@@ -1117,4 +996,9 @@ public class Listing extends AbstractStoreOperation {
     }
   }
 
+  public static RemoteIterator<LocatedFileStatus> toLocatedFileStatusIterator(
+      RemoteIterator<? extends LocatedFileStatus> iterator) {
+    return (RemoteIterator < LocatedFileStatus >) iterator;
+  }
+
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/S3ABlockOutputStream.java

@@ -20,6 +20,8 @@ package org.apache.hadoop.fs.s3a;
 
 import java.io.IOException;
 import java.io.OutputStream;
+import java.time.Duration;
+import java.time.Instant;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
@@ -49,10 +51,15 @@ import org.apache.hadoop.fs.PathIOException;
 import org.apache.hadoop.fs.StreamCapabilities;
 import org.apache.hadoop.fs.s3a.commit.CommitConstants;
 import org.apache.hadoop.fs.s3a.commit.PutTracker;
+import org.apache.hadoop.fs.s3a.statistics.BlockOutputStreamStatistics;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.fs.statistics.IOStatisticsLogging;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
 import org.apache.hadoop.util.Progressable;
 
 import static org.apache.hadoop.fs.s3a.S3AUtils.*;
 import static org.apache.hadoop.fs.s3a.Statistic.*;
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.emptyStatistics;
 import static org.apache.hadoop.io.IOUtils.cleanupWithLogger;
 
 /**
@@ -67,7 +74,7 @@ import static org.apache.hadoop.io.IOUtils.cleanupWithLogger;
 @InterfaceAudience.Private
 @InterfaceStability.Unstable
 class S3ABlockOutputStream extends OutputStream implements
-    StreamCapabilities {
+    StreamCapabilities, IOStatisticsSource {
 
   private static final Logger LOG =
       LoggerFactory.getLogger(S3ABlockOutputStream.class);
@@ -81,6 +88,9 @@ class S3ABlockOutputStream extends OutputStream implements
   /** Size of all blocks. */
   private final int blockSize;
 
+  /** IO Statistics. */
+  private final IOStatistics iostatistics;
+
   /** Total bytes for uploads submitted so far. */
   private long bytesSubmitted;
 
@@ -109,7 +119,7 @@ class S3ABlockOutputStream extends OutputStream implements
   private long blockCount = 0;
 
   /** Statistics to build up. */
-  private final S3AInstrumentation.OutputStreamStatistics statistics;
+  private final BlockOutputStreamStatistics statistics;
 
   /**
    * Write operation helper; encapsulation of the filesystem operations.
@@ -146,7 +156,7 @@ class S3ABlockOutputStream extends OutputStream implements
       Progressable progress,
       long blockSize,
       S3ADataBlocks.BlockFactory blockFactory,
-      S3AInstrumentation.OutputStreamStatistics statistics,
+      BlockOutputStreamStatistics statistics,
       WriteOperationHelper writeOperationHelper,
       PutTracker putTracker)
       throws IOException {
@@ -155,6 +165,10 @@ class S3ABlockOutputStream extends OutputStream implements
     this.blockFactory = blockFactory;
     this.blockSize = (int) blockSize;
     this.statistics = statistics;
+    // test instantiations may not provide statistics;
+    this.iostatistics = statistics != null
+        ? statistics.getIOStatistics()
+        : emptyStatistics();
     this.writeOperationHelper = writeOperationHelper;
     this.putTracker = putTracker;
     Preconditions.checkArgument(blockSize >= Constants.MULTIPART_MIN_SIZE,
@@ -282,6 +296,7 @@ class S3ABlockOutputStream extends OutputStream implements
     if (len == 0) {
       return;
     }
+    statistics.writeBytes(len);
     S3ADataBlocks.DataBlock block = createBlockIfNeeded();
     int written = block.write(source, offset, len);
     int remainingCapacity = block.remainingCapacity();
@@ -382,7 +397,8 @@ class S3ABlockOutputStream extends OutputStream implements
         // then complete the operation
         if (putTracker.aboutToComplete(multiPartUpload.getUploadId(),
             partETags,
-            bytes)) {
+            bytes,
+            iostatistics)) {
           multiPartUpload.complete(partETags);
         } else {
           LOG.info("File {} will be visible when the job is committed", key);
@@ -432,10 +448,9 @@ class S3ABlockOutputStream extends OutputStream implements
         writeOperationHelper.createPutObjectRequest(key, uploadData.getFile())
         : writeOperationHelper.createPutObjectRequest(key,
             uploadData.getUploadStream(), size);
-    long transferQueueTime = now();
     BlockUploadProgress callback =
         new BlockUploadProgress(
-            block, progressListener, transferQueueTime);
+            block, progressListener,  now());
     putObjectRequest.setGeneralProgressListener(callback);
     statistics.blockUploadQueued(size);
     ListenableFuture<PutObjectResult> putObjectResult =
@@ -473,6 +488,8 @@ class S3ABlockOutputStream extends OutputStream implements
     if (block != null) {
       sb.append(", activeBlock=").append(block);
     }
+    sb.append(" Statistics=")
+        .append(IOStatisticsLogging.ioStatisticsSourceToString(this));
     sb.append('}');
     return sb.toString();
   }
@@ -485,15 +502,15 @@ class S3ABlockOutputStream extends OutputStream implements
    * Current time in milliseconds.
    * @return time
    */
-  private long now() {
-    return System.currentTimeMillis();
+  private Instant now() {
+    return Instant.now();
   }
 
   /**
    * Get the statistics for this stream.
    * @return stream statistics
    */
-  S3AInstrumentation.OutputStreamStatistics getStatistics() {
+  BlockOutputStreamStatistics getStatistics() {
     return statistics;
   }
 
@@ -520,11 +537,20 @@ class S3ABlockOutputStream extends OutputStream implements
     case StreamCapabilities.HSYNC:
       return false;
 
+      // yes, we do statistics.
+    case StreamCapabilities.IOSTATISTICS:
+      return true;
+
     default:
       return false;
     }
   }
 
+  @Override
+  public IOStatistics getIOStatistics() {
+    return iostatistics;
+  }
+
   /**
    * Multiple partition upload.
    */
@@ -636,10 +662,9 @@ class S3ABlockOutputStream extends OutputStream implements
         noteUploadFailure(e);
         throw e;
       }
-      long transferQueueTime = now();
       BlockUploadProgress callback =
           new BlockUploadProgress(
-              block, progressListener, transferQueueTime);
+              block, progressListener, now());
       request.setGeneralProgressListener(callback);
       statistics.blockUploadQueued(block.dataSize());
       ListenableFuture<PartETag> partETagFuture =
@@ -754,8 +779,8 @@ class S3ABlockOutputStream extends OutputStream implements
   private final class BlockUploadProgress implements ProgressListener {
     private final S3ADataBlocks.DataBlock block;
     private final ProgressListener nextListener;
-    private final long transferQueueTime;
-    private long transferStartTime;
+    private final Instant transferQueueTime;
+    private Instant transferStartTime;
 
     /**
      * Track the progress of a single block upload.
@@ -766,7 +791,7 @@ class S3ABlockOutputStream extends OutputStream implements
      */
     private BlockUploadProgress(S3ADataBlocks.DataBlock block,
         ProgressListener nextListener,
-        long transferQueueTime) {
+        Instant transferQueueTime) {
       this.block = block;
       this.transferQueueTime = transferQueueTime;
       this.nextListener = nextListener;
@@ -787,17 +812,22 @@ class S3ABlockOutputStream extends OutputStream implements
 
       case TRANSFER_PART_STARTED_EVENT:
         transferStartTime = now();
-        statistics.blockUploadStarted(transferStartTime - transferQueueTime,
+        statistics.blockUploadStarted(
+            Duration.between(transferQueueTime, transferStartTime),
             size);
         incrementWriteOperations();
         break;
 
       case TRANSFER_PART_COMPLETED_EVENT:
-        statistics.blockUploadCompleted(now() - transferStartTime, size);
+        statistics.blockUploadCompleted(
+            Duration.between(transferStartTime, now()),
+            size);
         break;
 
       case TRANSFER_PART_FAILED_EVENT:
-        statistics.blockUploadFailed(now() - transferStartTime, size);
+        statistics.blockUploadFailed(
+            Duration.between(transferStartTime, now()),
+            size);
         LOG.warn("Transfer failure of block {}", block);
         break;
 

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/S3ADataBlocks.java

@@ -37,6 +37,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import org.apache.hadoop.fs.FSExceptionMessages;
+import org.apache.hadoop.fs.s3a.statistics.BlockOutputStreamStatistics;
 import org.apache.hadoop.util.DirectBufferPool;
 
 import static org.apache.hadoop.fs.s3a.S3ADataBlocks.DataBlock.DestState.*;
@@ -180,7 +181,7 @@ final class S3ADataBlocks {
      * @return a new block.
      */
     abstract DataBlock create(long index, int limit,
-        S3AInstrumentation.OutputStreamStatistics statistics)
+        BlockOutputStreamStatistics statistics)
         throws IOException;
 
     /**
@@ -210,10 +211,10 @@ final class S3ADataBlocks {
 
     private volatile DestState state = Writing;
     protected final long index;
-    protected final S3AInstrumentation.OutputStreamStatistics statistics;
+    private final BlockOutputStreamStatistics statistics;
 
     protected DataBlock(long index,
-        S3AInstrumentation.OutputStreamStatistics statistics) {
+        BlockOutputStreamStatistics statistics) {
       this.index = index;
       this.statistics = statistics;
     }
@@ -372,6 +373,10 @@ final class S3ADataBlocks {
         statistics.blockReleased();
       }
     }
+
+    protected BlockOutputStreamStatistics getStatistics() {
+      return statistics;
+    }
   }
 
   // ====================================================================
@@ -387,7 +392,7 @@ final class S3ADataBlocks {
 
     @Override
     DataBlock create(long index, int limit,
-        S3AInstrumentation.OutputStreamStatistics statistics)
+        BlockOutputStreamStatistics statistics)
         throws IOException {
       return new ByteArrayBlock(0, limit, statistics);
     }
@@ -432,7 +437,7 @@ final class S3ADataBlocks {
 
     ByteArrayBlock(long index,
         int limit,
-        S3AInstrumentation.OutputStreamStatistics statistics) {
+        BlockOutputStreamStatistics statistics) {
       super(index, statistics);
       this.limit = limit;
       buffer = new S3AByteArrayOutputStream(limit);
@@ -510,7 +515,7 @@ final class S3ADataBlocks {
 
     @Override
     ByteBufferBlock create(long index, int limit,
-        S3AInstrumentation.OutputStreamStatistics statistics)
+        BlockOutputStreamStatistics statistics)
         throws IOException {
       return new ByteBufferBlock(index, limit, statistics);
     }
@@ -560,7 +565,7 @@ final class S3ADataBlocks {
        */
       ByteBufferBlock(long index,
           int bufferSize,
-          S3AInstrumentation.OutputStreamStatistics statistics) {
+          BlockOutputStreamStatistics statistics) {
         super(index, statistics);
         this.bufferSize = bufferSize;
         blockBuffer = requestBuffer(bufferSize);
@@ -805,7 +810,7 @@ final class S3ADataBlocks {
     @Override
     DataBlock create(long index,
         int limit,
-        S3AInstrumentation.OutputStreamStatistics statistics)
+        BlockOutputStreamStatistics statistics)
         throws IOException {
       File destFile = getOwner()
           .createTmpFileForWrite(String.format("s3ablock-%04d-", index),
@@ -829,7 +834,7 @@ final class S3ADataBlocks {
     DiskBlock(File bufferFile,
         int limit,
         long index,
-        S3AInstrumentation.OutputStreamStatistics statistics)
+        BlockOutputStreamStatistics statistics)
         throws FileNotFoundException {
       super(index, statistics);
       this.limit = limit;

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/S3AFileSystem.java

@@ -117,11 +117,14 @@ import org.apache.hadoop.fs.s3a.impl.S3AMultipartUploaderBuilder;
 import org.apache.hadoop.fs.s3a.impl.StatusProbeEnum;
 import org.apache.hadoop.fs.s3a.impl.StoreContext;
 import org.apache.hadoop.fs.s3a.impl.StoreContextBuilder;
-import org.apache.hadoop.fs.s3a.impl.statistics.S3AMultipartUploaderStatisticsImpl;
 import org.apache.hadoop.fs.s3a.s3guard.BulkOperationState;
 import org.apache.hadoop.fs.s3a.select.InternalSelectConstants;
 import org.apache.hadoop.fs.s3a.tools.MarkerToolOperations;
 import org.apache.hadoop.fs.s3a.tools.MarkerToolOperationsImpl;
+import org.apache.hadoop.fs.statistics.DurationTracker;
+import org.apache.hadoop.fs.statistics.DurationTrackerFactory;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.io.Text;
 import org.apache.hadoop.security.token.DelegationTokenIssuer;
@@ -159,6 +162,11 @@ import org.apache.hadoop.fs.s3a.s3guard.MetadataStore;
 import org.apache.hadoop.fs.s3a.s3guard.PathMetadata;
 import org.apache.hadoop.fs.s3a.s3guard.S3Guard;
 import org.apache.hadoop.fs.s3a.s3guard.ITtlTimeProvider;
+import org.apache.hadoop.fs.s3a.statistics.BlockOutputStreamStatistics;
+import org.apache.hadoop.fs.s3a.statistics.CommitterStatistics;
+import org.apache.hadoop.fs.s3a.statistics.S3AStatisticsContext;
+import org.apache.hadoop.fs.s3a.statistics.StatisticsFromAwsSdk;
+import org.apache.hadoop.fs.s3a.statistics.impl.BondedS3AStatisticsContext;
 import org.apache.hadoop.fs.s3native.S3xLoginHelper;
 import org.apache.hadoop.io.retry.RetryPolicies;
 import org.apache.hadoop.fs.store.EtagChecksum;
@@ -170,10 +178,12 @@ import org.apache.hadoop.util.ReflectionUtils;
 import org.apache.hadoop.util.SemaphoredDelegatingExecutor;
 import org.apache.hadoop.util.concurrent.HadoopExecutors;
 
+import static java.util.Objects.requireNonNull;
 import static org.apache.hadoop.fs.impl.AbstractFSBuilderImpl.rejectUnknownMandatoryKeys;
 import static org.apache.hadoop.fs.impl.PathCapabilitiesSupport.validatePathCapabilityArgs;
 import static org.apache.hadoop.fs.s3a.Constants.*;
 import static org.apache.hadoop.fs.s3a.Invoker.*;
+import static org.apache.hadoop.fs.s3a.Listing.toLocatedFileStatusIterator;
 import static org.apache.hadoop.fs.s3a.S3AUtils.*;
 import static org.apache.hadoop.fs.s3a.Statistic.*;
 import static org.apache.commons.lang3.StringUtils.isNotEmpty;
@@ -185,12 +195,20 @@ import static org.apache.hadoop.fs.s3a.commit.CommitConstants.FS_S3A_COMMITTER_A
 import static org.apache.hadoop.fs.s3a.commit.CommitConstants.FS_S3A_COMMITTER_STAGING_ABORT_PENDING_UPLOADS;
 import static org.apache.hadoop.fs.s3a.impl.CallableSupplier.submit;
 import static org.apache.hadoop.fs.s3a.impl.CallableSupplier.waitForCompletionIgnoringExceptions;
+import static org.apache.hadoop.fs.s3a.impl.ErrorTranslation.isObjectNotFound;
 import static org.apache.hadoop.fs.s3a.impl.ErrorTranslation.isUnknownBucket;
+import static org.apache.hadoop.fs.s3a.impl.InternalConstants.AWS_SDK_METRICS_ENABLED;
 import static org.apache.hadoop.fs.s3a.impl.InternalConstants.SC_404;
 import static org.apache.hadoop.fs.s3a.impl.NetworkBinding.fixBucketRegion;
 import static org.apache.hadoop.fs.s3a.impl.NetworkBinding.logDnsLookup;
 import static org.apache.hadoop.fs.s3a.s3guard.S3Guard.dirMetaToStatuses;
+import static org.apache.hadoop.fs.statistics.StoreStatisticNames.OBJECT_CONTINUE_LIST_REQUEST;
+import static org.apache.hadoop.fs.statistics.StoreStatisticNames.OBJECT_LIST_REQUEST;
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.pairedTrackerFactory;
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.trackDurationOfInvocation;
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.trackDurationOfOperation;
 import static org.apache.hadoop.io.IOUtils.cleanupWithLogger;
+import static org.apache.hadoop.util.functional.RemoteIterators.typeCastingRemoteIterator;
 
 /**
  * The core S3A Filesystem implementation.
@@ -208,7 +226,7 @@ import static org.apache.hadoop.io.IOUtils.cleanupWithLogger;
 @InterfaceAudience.Private
 @InterfaceStability.Evolving
 public class S3AFileSystem extends FileSystem implements StreamCapabilities,
-    AWSPolicyProvider, DelegationTokenProvider {
+    AWSPolicyProvider, DelegationTokenProvider, IOStatisticsSource {
   /**
    * Default blocksize as used in blocksize and FS status queries.
    */
@@ -260,9 +278,13 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
    * is no encryption.
    */
   private EncryptionSecrets encryptionSecrets = new EncryptionSecrets();
+  /** The core instrumentation. */
   private S3AInstrumentation instrumentation;
-  private final S3AStorageStatistics storageStatistics =
-      createStorageStatistics();
+  /** Accessors to statistics for this FS. */
+  private S3AStatisticsContext statisticsContext;
+  /** Storage Statistics Bonded to the instrumentation. */
+  private S3AStorageStatistics storageStatistics;
+
   private long readAhead;
   private S3AInputPolicy inputPolicy;
   private ChangeDetectionPolicy changeDetectionPolicy;
@@ -369,6 +391,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
 
       invoker = new Invoker(new S3ARetryPolicy(getConf()), onRetry);
       instrumentation = new S3AInstrumentation(uri);
+      initializeStatisticsBinding();
 
       // Username is the current user at the time the FS was instantiated.
       owner = UserGroupInformation.getCurrentUser();
@@ -378,7 +401,8 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
 
       s3guardInvoker = new Invoker(new S3GuardExistsRetryPolicy(getConf()),
           onRetry);
-      writeHelper = new WriteOperationHelper(this, getConf());
+      writeHelper = new WriteOperationHelper(this, getConf(),
+          statisticsContext);
 
       failOnMetadataWriteError = conf.getBoolean(FAIL_ON_METADATA_WRITE_ERROR,
           FAIL_ON_METADATA_WRITE_ERROR_DEFAULT);
@@ -532,6 +556,33 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
     }
   }
 
+  /**
+   * Initialize the statistics binding.
+   * This is done by creating an {@code IntegratedS3AStatisticsContext}
+   * with callbacks to get the FS's instrumentation and FileSystem.statistics
+   * field; the latter may change after {@link #initialize(URI, Configuration)},
+   * so needs to be dynamically adapted.
+   * Protected so that (mock) subclasses can replace it with a
+   * different statistics binding, if desired.
+   */
+  protected void initializeStatisticsBinding() {
+    storageStatistics = createStorageStatistics(
+        requireNonNull(getIOStatistics()));
+    statisticsContext = new BondedS3AStatisticsContext(
+        new BondedS3AStatisticsContext.S3AFSStatisticsSource() {
+
+          @Override
+          public S3AInstrumentation getInstrumentation() {
+            return S3AFileSystem.this.getInstrumentation();
+          }
+
+          @Override
+          public Statistics getInstanceStatistics() {
+            return S3AFileSystem.this.statistics;
+          }
+        });
+  }
+
   /**
    * Initialize the thread pool.
    * This must be re-invoked after replacing the S3Client during test
@@ -566,13 +617,15 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
 
   /**
    * Create the storage statistics or bind to an existing one.
-   * @return a storage statistics instance.
+   * @param ioStatistics IOStatistics to build the storage statistics from.
+   * @return a storage statistics instance; expected to be that of the FS.
    */
-  protected static S3AStorageStatistics createStorageStatistics() {
+  protected static S3AStorageStatistics createStorageStatistics(
+      final IOStatistics ioStatistics) {
     return (S3AStorageStatistics)
         GlobalStorageStatistics.INSTANCE
             .put(S3AStorageStatistics.NAME,
-                () -> new S3AStorageStatistics());
+                () -> new S3AStorageStatistics(ioStatistics));
   }
 
   /**
@@ -611,6 +664,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
    * Get S3A Instrumentation. For test purposes.
    * @return this instance's instrumentation.
    */
+  @VisibleForTesting
   public S3AInstrumentation getInstrumentation() {
     return instrumentation;
   }
@@ -678,8 +732,16 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
         S3_CLIENT_FACTORY_IMPL, DEFAULT_S3_CLIENT_FACTORY_IMPL,
         S3ClientFactory.class);
 
+    StatisticsFromAwsSdk awsStats = null;
+    //  TODO: HADOOP-16830 when the S3 client building code works
+    //   with different regions,
+    //   then non-null stats can be passed in here.
+    if (AWS_SDK_METRICS_ENABLED) {
+      awsStats = statisticsContext.newStatisticsFromAwsSdk();
+    }
+
     s3 = ReflectionUtils.newInstance(s3ClientFactoryClass, conf)
-        .createS3Client(getUri(), bucket, credentials, uaSuffix);
+        .createS3Client(getUri(), bucket, credentials, uaSuffix, awsStats);
   }
 
   /**
@@ -1177,7 +1239,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
         invoker,
         s3guardInvoker,
         statistics,
-        instrumentation,
+        statisticsContext,
         fileStatus,
         seekPolicy,
         changePolicy,
@@ -1274,15 +1336,19 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
     PutTracker putTracker =
         committerIntegration.createTracker(path, key);
     String destKey = putTracker.getDestKey();
+    final BlockOutputStreamStatistics outputStreamStatistics
+        = statisticsContext.newOutputStreamStatistics();
     return new FSDataOutputStream(
         new S3ABlockOutputStream(this,
             destKey,
-            new SemaphoredDelegatingExecutor(boundedThreadPool,
-                blockOutputActiveBlocks, true),
+            new SemaphoredDelegatingExecutor(
+                boundedThreadPool,
+                blockOutputActiveBlocks,
+                true),
             progress,
             partSize,
             blockFactory,
-            instrumentation.newOutputStreamStatistics(statistics),
+            outputStreamStatistics,
             getWriteOperationHelper(),
             putTracker),
         null);
@@ -1656,20 +1722,26 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
     @Override
     @Retries.RetryRaw
     public CompletableFuture<S3ListResult> listObjectsAsync(
-            S3ListRequest request)
+        S3ListRequest request,
+        DurationTrackerFactory trackerFactory)
             throws IOException {
-      return submit(unboundedThreadPool,
-        () -> listObjects(request));
+      return submit(unboundedThreadPool, () ->
+          listObjects(request,
+              pairedTrackerFactory(trackerFactory,
+                  getDurationTrackerFactory())));
     }
 
     @Override
     @Retries.RetryRaw
     public CompletableFuture<S3ListResult> continueListObjectsAsync(
-            S3ListRequest request,
-            S3ListResult prevResult)
+        S3ListRequest request,
+        S3ListResult prevResult,
+        DurationTrackerFactory trackerFactory)
             throws IOException {
       return submit(unboundedThreadPool,
-        () -> continueListObjects(request, prevResult));
+          () -> continueListObjects(request, prevResult,
+              pairedTrackerFactory(trackerFactory,
+                  getDurationTrackerFactory())));
     }
 
     @Override
@@ -1818,8 +1890,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
    * @param count the count to increment
    */
   protected void incrementStatistic(Statistic statistic, long count) {
-    instrumentation.incrementCounter(statistic, count);
-    storageStatistics.incrementCounter(statistic, count);
+    statisticsContext.incrementCounter(statistic, count);
   }
 
   /**
@@ -1828,7 +1899,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
    * @param count the count to decrement
    */
   protected void decrementGauge(Statistic statistic, long count) {
-    instrumentation.decrementGauge(statistic, count);
+    statisticsContext.decrementGauge(statistic, count);
   }
 
   /**
@@ -1837,7 +1908,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
    * @param count the count to increment
    */
   protected void incrementGauge(Statistic statistic, long count) {
-    instrumentation.incrementGauge(statistic, count);
+    statisticsContext.incrementGauge(statistic, count);
   }
 
   /**
@@ -1850,6 +1921,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
     if (isThrottleException(ex)) {
       operationThrottled(false);
     } else {
+      incrementStatistic(STORE_IO_RETRY);
       incrementStatistic(IGNORED_ERRORS);
     }
   }
@@ -1901,11 +1973,11 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
     LOG.debug("Request throttled on {}", metastore ? "S3": "DynamoDB");
     if (metastore) {
       incrementStatistic(S3GUARD_METADATASTORE_THROTTLED);
-      instrumentation.addValueToQuantiles(S3GUARD_METADATASTORE_THROTTLE_RATE,
+      statisticsContext.addValueToQuantiles(S3GUARD_METADATASTORE_THROTTLE_RATE,
           1);
     } else {
       incrementStatistic(STORE_IO_THROTTLED);
-      instrumentation.addValueToQuantiles(STORE_IO_THROTTLE_RATE, 1);
+      statisticsContext.addValueToQuantiles(STORE_IO_THROTTLE_RATE, 1);
     }
   }
 
@@ -1918,6 +1990,27 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
     return storageStatistics;
   }
 
+  /**
+   * Get the instrumentation's IOStatistics.
+   * @return statistics
+   */
+  @Override
+  public IOStatistics getIOStatistics() {
+    return instrumentation != null
+        ? instrumentation.getIOStatistics()
+        : null;
+  }
+
+  /**
+   * Get the factory for duration tracking.
+   * @return a factory from the instrumentation.
+   */
+  protected DurationTrackerFactory getDurationTrackerFactory() {
+    return instrumentation != null ?
+        instrumentation.getDurationTrackerFactory()
+        : null;
+  }
+
   /**
    * Request object metadata; increments counters in the process.
    * Retry policy: retry untranslated.
@@ -1955,15 +2048,30 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
     ObjectMetadata meta = changeInvoker.retryUntranslated("GET " + key, true,
         () -> {
           incrementStatistic(OBJECT_METADATA_REQUESTS);
-          LOG.debug("HEAD {} with change tracker {}", key, changeTracker);
-          if (changeTracker != null) {
-            changeTracker.maybeApplyConstraint(request);
-          }
-          ObjectMetadata objectMetadata = s3.getObjectMetadata(request);
-          if (changeTracker != null) {
-            changeTracker.processMetadata(objectMetadata, operation);
+          DurationTracker duration = getDurationTrackerFactory()
+              .trackDuration(ACTION_HTTP_HEAD_REQUEST.getSymbol());
+          try {
+            LOG.debug("HEAD {} with change tracker {}", key, changeTracker);
+            if (changeTracker != null) {
+              changeTracker.maybeApplyConstraint(request);
+            }
+            ObjectMetadata objectMetadata = s3.getObjectMetadata(request);
+            if (changeTracker != null) {
+              changeTracker.processMetadata(objectMetadata, operation);
+            }
+            return objectMetadata;
+          } catch(AmazonServiceException ase) {
+            if (!isObjectNotFound(ase)) {
+              // file not found is not considered a failure of the call,
+              // so only switch the duration tracker to update failure
+              // metrics on other exception outcomes.
+              duration.failed();
+            }
+            throw ase;
+          } finally {
+            // update the tracker.
+            duration.close();
           }
-          return objectMetadata;
         });
     incrementReadOperations();
     return meta;
@@ -1975,13 +2083,15 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
    *
    * Retry policy: retry untranslated.
    * @param request request to initiate
+   * @param trackerFactory duration tracking
    * @return the results
    * @throws IOException if the retry invocation raises one (it shouldn't).
    */
   @Retries.RetryRaw
-  protected S3ListResult listObjects(S3ListRequest request) throws IOException {
+  protected S3ListResult listObjects(S3ListRequest request,
+      @Nullable final DurationTrackerFactory trackerFactory)
+      throws IOException {
     incrementReadOperations();
-    incrementStatistic(OBJECT_LIST_REQUESTS);
     LOG.debug("LIST {}", request);
     validateListArguments(request);
     try(DurationInfo ignored =
@@ -1989,13 +2099,15 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
       return invoker.retryUntranslated(
           request.toString(),
           true,
-          () -> {
-            if (useListV1) {
-              return S3ListResult.v1(s3.listObjects(request.getV1()));
-            } else {
-              return S3ListResult.v2(s3.listObjectsV2(request.getV2()));
-            }
-          });
+          trackDurationOfOperation(trackerFactory,
+              OBJECT_LIST_REQUEST,
+              () -> {
+                if (useListV1) {
+                  return S3ListResult.v1(s3.listObjects(request.getV1()));
+                } else {
+                  return S3ListResult.v2(s3.listObjectsV2(request.getV2()));
+                }
+              }));
     }
   }
 
@@ -2016,12 +2128,14 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
    * Retry policy: retry untranslated.
    * @param request last list objects request to continue
    * @param prevResult last paged result to continue from
+   * @param trackerFactory duration tracking
    * @return the next result object
    * @throws IOException none, just there for retryUntranslated.
    */
   @Retries.RetryRaw
   protected S3ListResult continueListObjects(S3ListRequest request,
-      S3ListResult prevResult) throws IOException {
+      S3ListResult prevResult,
+      final DurationTrackerFactory trackerFactory) throws IOException {
     incrementReadOperations();
     validateListArguments(request);
     try(DurationInfo ignored =
@@ -2029,17 +2143,19 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
       return invoker.retryUntranslated(
           request.toString(),
           true,
-          () -> {
-            incrementStatistic(OBJECT_CONTINUE_LIST_REQUESTS);
-            if (useListV1) {
-              return S3ListResult.v1(
-                  s3.listNextBatchOfObjects(prevResult.getV1()));
-            } else {
-              request.getV2().setContinuationToken(prevResult.getV2()
-                  .getNextContinuationToken());
-              return S3ListResult.v2(s3.listObjectsV2(request.getV2()));
-            }
-          });
+          trackDurationOfOperation(
+              trackerFactory,
+              OBJECT_CONTINUE_LIST_REQUEST,
+              () -> {
+                if (useListV1) {
+                  return S3ListResult.v1(
+                      s3.listNextBatchOfObjects(prevResult.getV1()));
+                } else {
+                  request.getV2().setContinuationToken(prevResult.getV2()
+                      .getNextContinuationToken());
+                  return S3ListResult.v2(s3.listObjectsV2(request.getV2()));
+                }
+              }));
     }
   }
 
@@ -2084,9 +2200,10 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
       invoker.retryUntranslated(String.format("Delete %s:/%s", bucket, key),
           DELETE_CONSIDERED_IDEMPOTENT,
           ()-> {
-            incrementStatistic(OBJECT_DELETE_REQUESTS);
             incrementStatistic(OBJECT_DELETE_OBJECTS);
-            s3.deleteObject(bucket, key);
+            trackDurationOfInvocation(getDurationTrackerFactory(),
+                OBJECT_DELETE_REQUEST.getSymbol(),
+                () -> s3.deleteObject(bucket, key));
             return null;
           });
     }
@@ -2170,11 +2287,12 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
             // handle the failure
             retryHandler.bulkDeleteRetried(deleteRequest, e);
           },
-          () -> {
-            incrementStatistic(OBJECT_DELETE_REQUESTS, 1);
-            incrementStatistic(OBJECT_DELETE_OBJECTS, keyCount);
-            return s3.deleteObjects(deleteRequest);
-          });
+          // duration is tracked in the bulk delete counters
+          trackDurationOfOperation(getDurationTrackerFactory(),
+              OBJECT_BULK_DELETE_REQUEST.getSymbol(), () -> {
+                incrementStatistic(OBJECT_DELETE_OBJECTS, keyCount);
+                return s3.deleteObjects(deleteRequest);
+            }));
     } catch (MultiObjectDeleteException e) {
       // one or more of the keys could not be deleted.
       // log and rethrow
@@ -2666,17 +2784,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
           throws FileNotFoundException, IOException {
     RemoteIterator<S3AFileStatus> listStatusItr = once("listStatus",
             p.toString(), () -> innerListStatus(p));
-    return new RemoteIterator<FileStatus>() {
-      @Override
-      public boolean hasNext() throws IOException {
-        return listStatusItr.hasNext();
-      }
-
-      @Override
-      public FileStatus next() throws IOException {
-        return listStatusItr.next();
-      }
-    };
+    return typeCastingRemoteIterator(listStatusItr);
   }
 
   /**
@@ -3202,8 +3310,8 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
         S3ListRequest request = createListObjectsRequest(dirKey, "/",
             listSize);
         // execute the request
-        S3ListResult listResult = listObjects(request);
-
+        S3ListResult listResult = listObjects(request,
+            getDurationTrackerFactory());
 
         if (listResult.hasPrefixesOrObjects(contextAccessors, tombstones)) {
           if (LOG.isDebugEnabled()) {
@@ -3608,8 +3716,9 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
     ChangeTracker changeTracker = new ChangeTracker(
         keyToQualifiedPath(srcKey).toString(),
         changeDetectionPolicy,
-        readContext.instrumentation.newInputStreamStatistics()
-            .getVersionMismatchCounter(),
+        readContext.getS3AStatisticsContext()
+            .newInputStreamStatistics()
+            .getChangeTrackerStatistics(),
         srcAttributes);
 
     String action = "copyFile(" + srcKey + ", " + dstKey + ")";
@@ -4103,12 +4212,10 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
     sb.append(", delegation tokens=")
         .append(delegationTokens.map(Objects::toString).orElse("disabled"));
     sb.append(", ").append(directoryPolicy);
-    sb.append(", statistics {")
-        .append(statistics)
-        .append("}");
-    if (instrumentation != null) {
-      sb.append(", metrics {")
-          .append(instrumentation.dump("{", "=", "} ", true))
+    // if logging at debug, toString returns the entire IOStatistics set.
+    if (getInstrumentation() != null) {
+      sb.append(", instrumentation {")
+          .append(getInstrumentation().toString())
           .append("}");
     }
     sb.append('}');
@@ -4308,21 +4415,6 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
         new Listing.AcceptFilesOnly(qualify(f)), null, true, false));
   }
 
-  private static RemoteIterator<LocatedFileStatus> toLocatedFileStatusIterator(
-      RemoteIterator<? extends LocatedFileStatus> iterator) {
-    return new RemoteIterator<LocatedFileStatus>() {
-      @Override
-      public boolean hasNext() throws IOException {
-        return iterator.hasNext();
-      }
-
-      @Override
-      public LocatedFileStatus next() throws IOException {
-        return iterator.next();
-      }
-    };
-  }
-
   /**
    * Recursive List of files and empty directories.
    * @param f path to list from
@@ -4405,7 +4497,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
       if (status != null && status.isFile()) {
         // simple case: File
         LOG.debug("Path is a file: {}", path);
-        return new Listing.SingleStatusRemoteIterator(
+        return listing.createSingleStatusIterator(
             toLocatedFileStatus(status));
       }
       // Assuming the path to be a directory
@@ -4425,7 +4517,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
                 ? status
                 : (S3AFileStatus) getFileStatus(path);
         if (fileStatus.isFile()) {
-          return new Listing.SingleStatusRemoteIterator(
+          return listing.createSingleStatusIterator(
                   toLocatedFileStatus(fileStatus));
         }
       }
@@ -4484,7 +4576,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
               if (fileStatus.isFile()) {
                 // simple case: File
                 LOG.debug("Path is a file");
-                return new Listing.SingleStatusRemoteIterator(
+                return listing.createSingleStatusIterator(
                         filter.accept(path)
                                 ? toLocatedFileStatus(fileStatus)
                                 : null);
@@ -4631,8 +4723,8 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
    * Create a new instance of the committer statistics.
    * @return a new committer statistics instance
    */
-  public S3AInstrumentation.CommitterStatistics newCommitterStatistics() {
-    return instrumentation.newCommitterStatistics();
+  public CommitterStatistics newCommitterStatistics() {
+    return statisticsContext.newCommitterStatistics();
   }
 
   @SuppressWarnings("deprecation")
@@ -4766,8 +4858,9 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
       ChangeTracker changeTracker =
           new ChangeTracker(uri.toString(),
               changeDetectionPolicy,
-              readContext.instrumentation.newInputStreamStatistics()
-                  .getVersionMismatchCounter(),
+              readContext.getS3AStatisticsContext()
+                  .newInputStreamStatistics()
+                  .getChangeTrackerStatistics(),
               objectAttributes);
 
       // will retry internally if wrong version detected
@@ -4914,7 +5007,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
         getWriteOperationHelper(),
         ctx,
         basePath,
-        new S3AMultipartUploaderStatisticsImpl(ctx::incrementStatistic));
+        statisticsContext.createMultipartUploaderStatistics());
   }
 
   /**
@@ -4934,7 +5027,7 @@ public class S3AFileSystem extends FileSystem implements StreamCapabilities,
         .setExecutor(boundedThreadPool)
         .setExecutorCapacity(executorCapacity)
         .setInvoker(invoker)
-        .setInstrumentation(getInstrumentation())
+        .setInstrumentation(statisticsContext)
         .setStorageStatistics(getStorageStatistics())
         .setInputPolicy(getInputPolicy())
         .setChangeDetectionPolicy(changeDetectionPolicy)

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/S3AInputStream.java

@@ -33,10 +33,14 @@ import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.fs.CanSetReadahead;
 import org.apache.hadoop.fs.CanUnbuffer;
 import org.apache.hadoop.fs.FSExceptionMessages;
-import org.apache.hadoop.fs.FSInputStream;
+import org.apache.hadoop.fs.s3a.statistics.S3AInputStreamStatistics;
+import org.apache.hadoop.fs.s3a.impl.ChangeTracker;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
 import org.apache.hadoop.fs.PathIOException;
 import org.apache.hadoop.fs.StreamCapabilities;
-import org.apache.hadoop.fs.s3a.impl.ChangeTracker;
+import org.apache.hadoop.fs.FSInputStream;
+import org.apache.hadoop.fs.statistics.DurationTracker;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -68,7 +72,7 @@ import static org.apache.hadoop.util.StringUtils.toLowerCase;
 @InterfaceAudience.Private
 @InterfaceStability.Evolving
 public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
-        CanUnbuffer, StreamCapabilities {
+        CanUnbuffer, StreamCapabilities, IOStatisticsSource {
 
   public static final String E_NEGATIVE_READAHEAD_VALUE
       = "Negative readahead value";
@@ -105,7 +109,7 @@ public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
   private final String uri;
   private static final Logger LOG =
       LoggerFactory.getLogger(S3AInputStream.class);
-  private final S3AInstrumentation.InputStreamStatistics streamStatistics;
+  private final S3AInputStreamStatistics streamStatistics;
   private S3AEncryptionMethods serverSideEncryptionAlgorithm;
   private String serverSideEncryptionKey;
   private S3AInputPolicy inputPolicy;
@@ -131,6 +135,11 @@ public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
   /** change tracker. */
   private final ChangeTracker changeTracker;
 
+  /**
+   * IOStatistics report.
+   */
+  private final IOStatistics ioStatistics;
+
   /**
    * Create the stream.
    * This does not attempt to open it; that is only done on the first
@@ -154,13 +163,15 @@ public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
     this.contentLength = l;
     this.client = client;
     this.uri = "s3a://" + this.bucket + "/" + this.key;
-    this.streamStatistics = ctx.instrumentation.newInputStreamStatistics();
+    this.streamStatistics = ctx.getS3AStatisticsContext()
+        .newInputStreamStatistics();
+    this.ioStatistics = streamStatistics.getIOStatistics();
     this.serverSideEncryptionAlgorithm =
         s3Attributes.getServerSideEncryptionAlgorithm();
     this.serverSideEncryptionKey = s3Attributes.getServerSideEncryptionKey();
     this.changeTracker = new ChangeTracker(uri,
         ctx.getChangeDetectionPolicy(),
-        streamStatistics.getVersionMismatchCounter(),
+        streamStatistics.getChangeTrackerStatistics(),
         s3Attributes);
     setInputPolicy(ctx.getInputPolicy());
     setReadahead(ctx.getReadahead());
@@ -210,8 +221,21 @@ public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
     String text = String.format("%s %s at %d",
         operation, uri, targetPos);
     changeTracker.maybeApplyConstraint(request);
-    object = Invoker.once(text, uri,
-        () -> client.getObject(request));
+    DurationTracker tracker = streamStatistics.initiateGetRequest();
+    try {
+      object = Invoker.once(text, uri,
+          () -> client.getObject(request));
+    } catch(IOException e) {
+      // input function failed: note it
+      tracker.failed();
+      // and rethrow
+      throw e;
+    } finally {
+      // update the tracker.
+      // this is called after any catch() call will have
+      // set the failed flag.
+      tracker.close();
+    }
 
     changeTracker.processResponse(object, operation,
         targetPos);
@@ -294,13 +318,11 @@ public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
       if (skipForward) {
         // the forward seek range is within the limits
         LOG.debug("Forward seek on {}, of {} bytes", uri, diff);
-        streamStatistics.seekForwards(diff);
         long skipped = wrappedStream.skip(diff);
         if (skipped > 0) {
           pos += skipped;
-          // as these bytes have been read, they are included in the counter
-          incrementBytesRead(diff);
         }
+        streamStatistics.seekForwards(diff, skipped);
 
         if (pos == targetPos) {
           // all is well
@@ -312,6 +334,9 @@ public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
           LOG.warn("Failed to seek on {} to {}. Current position {}",
               uri, targetPos,  pos);
         }
+      } else {
+        // not attempting to read any bytes from the stream
+        streamStatistics.seekForwards(diff, 0);
       }
     } else if (diff < 0) {
       // backwards seek
@@ -356,7 +381,7 @@ public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
     // open.  After that, an exception generally means the file has changed
     // and there is no point retrying anymore.
     Invoker invoker = context.getReadInvoker();
-    invoker.maybeRetry(streamStatistics.openOperations == 0,
+    invoker.maybeRetry(streamStatistics.getOpenOperations() == 0,
         "lazySeek", pathStr, true,
         () -> {
           //For lazy seek
@@ -720,7 +745,7 @@ public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
       sb.append(" contentRangeFinish=").append(contentRangeFinish);
       sb.append(" remainingInCurrentRequest=")
           .append(remainingInCurrentRequest());
-      sb.append(changeTracker);
+      sb.append(" ").append(changeTracker);
       sb.append('\n').append(s);
       sb.append('}');
       return sb.toString();
@@ -774,7 +799,7 @@ public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
    */
   @InterfaceAudience.Private
   @InterfaceStability.Unstable
-  public S3AInstrumentation.InputStreamStatistics getS3AStreamStatistics() {
+  public S3AInputStreamStatistics getS3AStreamStatistics() {
     return streamStatistics;
   }
 
@@ -858,13 +883,14 @@ public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
     try {
       closeStream("unbuffer()", contentRangeFinish, false);
     } finally {
-      streamStatistics.merge(false);
+      streamStatistics.unbuffered();
     }
   }
 
   @Override
   public boolean hasCapability(String capability) {
     switch (toLowerCase(capability)) {
+    case StreamCapabilities.IOSTATISTICS:
     case StreamCapabilities.READAHEAD:
     case StreamCapabilities.UNBUFFER:
       return true;
@@ -877,4 +903,9 @@ public class S3AInputStream extends FSInputStream implements  CanSetReadahead,
   boolean isObjectStreamOpen() {
     return wrappedStream != null;
   }
+
+  @Override
+  public IOStatistics getIOStatistics() {
+    return ioStatistics;
+  }
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/S3AOpContext.java

@@ -24,19 +24,23 @@ import org.apache.hadoop.thirdparty.com.google.common.base.Preconditions;
 
 import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.s3a.impl.ActiveOperationContext;
+import org.apache.hadoop.fs.s3a.statistics.S3AStatisticsContext;
 
 /**
- * Base class for operation context struct passed through codepaths for main
+ * Class for operation context struct passed through codepaths for main
  * S3AFileSystem operations.
  * Anything op-specific should be moved to a subclass of this.
+ *
+ * This was originally a base class, but {@link ActiveOperationContext} was
+ * created to be more minimal and cover many more operation type.
  */
-@SuppressWarnings("visibilitymodifier")  // I want a struct of finals, for real.
-public class S3AOpContext {
+@SuppressWarnings("visibilitymodifier")
+public class S3AOpContext extends ActiveOperationContext {
 
   final boolean isS3GuardEnabled;
   final Invoker invoker;
   @Nullable final FileSystem.Statistics stats;
-  final S3AInstrumentation instrumentation;
   @Nullable final Invoker s3guardInvoker;
 
   /** FileStatus for "destination" path being operated on. */
@@ -53,9 +57,14 @@ public class S3AOpContext {
    * @param dstFileStatus file status from existence check
    */
   public S3AOpContext(boolean isS3GuardEnabled, Invoker invoker,
-      Invoker s3guardInvoker, @Nullable FileSystem.Statistics stats,
-      S3AInstrumentation instrumentation, FileStatus dstFileStatus) {
+      @Nullable Invoker s3guardInvoker,
+      @Nullable FileSystem.Statistics stats,
+      S3AStatisticsContext instrumentation,
+      FileStatus dstFileStatus) {
 
+    super(newOperationId(),
+        instrumentation,
+        null);
     Preconditions.checkNotNull(invoker, "Null invoker arg");
     Preconditions.checkNotNull(instrumentation, "Null instrumentation arg");
     Preconditions.checkNotNull(dstFileStatus, "Null dstFileStatus arg");
@@ -65,7 +74,6 @@ public class S3AOpContext {
     this.invoker = invoker;
     this.s3guardInvoker = s3guardInvoker;
     this.stats = stats;
-    this.instrumentation = instrumentation;
     this.dstFileStatus = dstFileStatus;
   }
 
@@ -77,8 +85,10 @@ public class S3AOpContext {
    * @param instrumentation instrumentation to use
    * @param dstFileStatus file status from existence check
    */
-  public S3AOpContext(boolean isS3GuardEnabled, Invoker invoker,
-      @Nullable FileSystem.Statistics stats, S3AInstrumentation instrumentation,
+  public S3AOpContext(boolean isS3GuardEnabled,
+      Invoker invoker,
+      @Nullable FileSystem.Statistics stats,
+      S3AStatisticsContext instrumentation,
       FileStatus dstFileStatus) {
     this(isS3GuardEnabled, invoker, null, stats, instrumentation,
         dstFileStatus);
@@ -97,10 +107,6 @@ public class S3AOpContext {
     return stats;
   }
 
-  public S3AInstrumentation getInstrumentation() {
-    return instrumentation;
-  }
-
   @Nullable
   public Invoker getS3guardInvoker() {
     return s3guardInvoker;

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/S3AReadOpContext.java

@@ -22,6 +22,7 @@ import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.s3a.impl.ChangeDetectionPolicy;
+import org.apache.hadoop.fs.s3a.statistics.S3AStatisticsContext;
 
 import javax.annotation.Nullable;
 
@@ -60,8 +61,8 @@ public class S3AReadOpContext extends S3AOpContext {
    * @param isS3GuardEnabled true iff S3Guard is enabled.
    * @param invoker invoker for normal retries.
    * @param s3guardInvoker S3Guard-specific retry invoker.
-   * @param stats statistics (may be null)
-   * @param instrumentation FS instrumentation
+   * @param stats Fileystem statistics (may be null)
+   * @param instrumentation statistics context
    * @param dstFileStatus target file status
    * @param inputPolicy the input policy
    * @param readahead readahead for GET operations/skip, etc.
@@ -71,13 +72,14 @@ public class S3AReadOpContext extends S3AOpContext {
       final Path path,
       boolean isS3GuardEnabled,
       Invoker invoker,
-      Invoker s3guardInvoker,
+      @Nullable Invoker s3guardInvoker,
       @Nullable FileSystem.Statistics stats,
-      S3AInstrumentation instrumentation,
+      S3AStatisticsContext instrumentation,
       FileStatus dstFileStatus,
       S3AInputPolicy inputPolicy,
       ChangeDetectionPolicy changeDetectionPolicy,
       final long readahead) {
+
     super(isS3GuardEnabled, invoker, s3guardInvoker, stats, instrumentation,
         dstFileStatus);
     this.path = checkNotNull(path);

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/S3AStorageStatistics.java

@@ -20,106 +20,27 @@ package org.apache.hadoop.fs.s3a;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
-import org.apache.hadoop.fs.StorageStatistics;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.fs.statistics.impl.StorageStatisticsFromIOStatistics;
 
-import java.util.Collections;
-import java.util.EnumMap;
-import java.util.Iterator;
-import java.util.Map;
-import java.util.NoSuchElementException;
-import java.util.concurrent.atomic.AtomicLong;
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.emptyStatistics;
 
 /**
- * Storage statistics for S3A.
+ * Storage statistics for S3A, dynamically generated from the IOStatistics.
  */
 @InterfaceAudience.Private
 @InterfaceStability.Evolving
-public class S3AStorageStatistics extends StorageStatistics
-    implements Iterable<StorageStatistics.LongStatistic> {
-  private static final Logger LOG =
-      LoggerFactory.getLogger(S3AStorageStatistics.class);
+public class S3AStorageStatistics
+    extends StorageStatisticsFromIOStatistics {
 
   public static final String NAME = "S3AStorageStatistics";
-  private final Map<Statistic, AtomicLong> opsCount =
-      new EnumMap<>(Statistic.class);
 
-  public S3AStorageStatistics() {
-    super(NAME);
-    for (Statistic opType : Statistic.values()) {
-      opsCount.put(opType, new AtomicLong(0));
-    }
-  }
-
-  /**
-   * Increment a specific counter.
-   * @param op operation
-   * @param count increment value
-   * @return the new value
-   */
-  public long incrementCounter(Statistic op, long count) {
-    long updated = opsCount.get(op).addAndGet(count);
-    LOG.debug("{} += {}  ->  {}", op, count, updated);
-    return updated;
-  }
-
-  private class LongIterator implements Iterator<LongStatistic> {
-    private Iterator<Map.Entry<Statistic, AtomicLong>> iterator =
-        Collections.unmodifiableSet(opsCount.entrySet()).iterator();
-
-    @Override
-    public boolean hasNext() {
-      return iterator.hasNext();
-    }
-
-    @Override
-    public LongStatistic next() {
-      if (!iterator.hasNext()) {
-        throw new NoSuchElementException();
-      }
-      final Map.Entry<Statistic, AtomicLong> entry = iterator.next();
-      return new LongStatistic(entry.getKey().getSymbol(),
-          entry.getValue().get());
-    }
-
-    @Override
-    public void remove() {
-      throw new UnsupportedOperationException();
-    }
-  }
-
-  @Override
-  public String getScheme() {
-    return "s3a";
+  public S3AStorageStatistics(final IOStatistics ioStatistics) {
+    super(NAME, "s3a", ioStatistics);
   }
 
-  @Override
-  public Iterator<LongStatistic> getLongStatistics() {
-    return new LongIterator();
-  }
-
-  @Override
-  public Iterator<LongStatistic> iterator() {
-    return getLongStatistics();
-  }
-
-  @Override
-  public Long getLong(String key) {
-    final Statistic type = Statistic.fromSymbol(key);
-    return type == null ? null : opsCount.get(type).get();
-  }
-
-  @Override
-  public boolean isTracked(String key) {
-    return Statistic.fromSymbol(key) != null;
-  }
-
-  @Override
-  public void reset() {
-    for (AtomicLong value : opsCount.values()) {
-      value.set(0);
-    }
+  public S3AStorageStatistics() {
+    super(NAME, "s3a", emptyStatistics());
   }
 
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/S3AUtils.java

@@ -48,6 +48,7 @@ import org.apache.hadoop.fs.LocatedFileStatus;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.PathFilter;
 import org.apache.hadoop.fs.RemoteIterator;
+import org.apache.hadoop.util.functional.RemoteIterators;
 import org.apache.hadoop.fs.s3a.auth.IAMInstanceCredentialsProvider;
 import org.apache.hadoop.fs.s3a.impl.NetworkBinding;
 import org.apache.hadoop.fs.s3native.S3xLoginHelper;
@@ -1470,12 +1471,7 @@ public final class S3AUtils {
   public static long applyLocatedFiles(
       RemoteIterator<? extends LocatedFileStatus> iterator,
       CallOnLocatedFileStatus eval) throws IOException {
-    long count = 0;
-    while (iterator.hasNext()) {
-      count++;
-      eval.call(iterator.next());
-    }
-    return count;
+    return RemoteIterators.foreach(iterator, eval::call);
   }
 
   /**

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/S3ClientFactory.java

@@ -26,6 +26,7 @@ import com.amazonaws.services.s3.AmazonS3;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
+import org.apache.hadoop.fs.s3a.statistics.StatisticsFromAwsSdk;
 
 /**
  * Factory for creation of {@link AmazonS3} client instances.
@@ -41,12 +42,14 @@ public interface S3ClientFactory {
    * @param bucket Optional bucket to use to look up per-bucket proxy secrets
    * @param credentialSet credentials to use
    * @param userAgentSuffix optional suffix for the UA field.
+   * @param statisticsFromAwsSdk binding for AWS stats - may be null
    * @return S3 client
    * @throws IOException IO problem
    */
   AmazonS3 createS3Client(URI name,
       String bucket,
       AWSCredentialsProvider credentialSet,
-      String userAgentSuffix) throws IOException;
+      String userAgentSuffix,
+      StatisticsFromAwsSdk statisticsFromAwsSdk) throws IOException;
 
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/Statistic.java

@@ -18,248 +18,504 @@
 
 package org.apache.hadoop.fs.s3a;
 
-import org.apache.hadoop.fs.StorageStatistics.CommonStatisticNames;
-
 import java.util.HashMap;
 import java.util.Map;
 
+import org.apache.hadoop.classification.InterfaceStability;
+import org.apache.hadoop.fs.s3a.statistics.StatisticTypeEnum;
+import org.apache.hadoop.fs.statistics.StoreStatisticNames;
+import org.apache.hadoop.fs.statistics.StreamStatisticNames;
+
+import static org.apache.hadoop.fs.s3a.statistics.StatisticTypeEnum.TYPE_COUNTER;
+import static org.apache.hadoop.fs.s3a.statistics.StatisticTypeEnum.TYPE_DURATION;
+import static org.apache.hadoop.fs.s3a.statistics.StatisticTypeEnum.TYPE_GAUGE;
+import static org.apache.hadoop.fs.s3a.statistics.StatisticTypeEnum.TYPE_QUANTILE;
+
 /**
  * Statistic which are collected in S3A.
- * These statistics are available at a low level in {@link S3AStorageStatistics}
- * and as metrics in {@link S3AInstrumentation}
+ * Counter and duration statistics are published in
+ * {@link S3AFileSystem#getStorageStatistics()}.
+ * and as metrics in {@link S3AInstrumentation}.
+ * <p>
+ * Where possible, stream names come from {@link StreamStatisticNames}
+ * and {@link StoreStatisticNames}
+ * </p>
  */
+@InterfaceStability.Unstable
 public enum Statistic {
 
+  /* Low-level duration counters */
+  ACTION_EXECUTOR_ACQUIRED(
+      StoreStatisticNames.ACTION_EXECUTOR_ACQUIRED,
+      "Executor acquired.",
+      TYPE_DURATION),
+  ACTION_HTTP_HEAD_REQUEST(
+      StoreStatisticNames.ACTION_HTTP_HEAD_REQUEST,
+      "HEAD request.",
+      TYPE_DURATION),
+  ACTION_HTTP_GET_REQUEST(
+      StoreStatisticNames.ACTION_HTTP_GET_REQUEST,
+      "GET request.",
+      TYPE_DURATION),
+
+  /* FileSystem Level statistics */
   DIRECTORIES_CREATED("directories_created",
-      "Total number of directories created through the object store."),
+      "Total number of directories created through the object store.",
+      TYPE_COUNTER),
   DIRECTORIES_DELETED("directories_deleted",
-      "Total number of directories deleted through the object store."),
+      "Total number of directories deleted through the object store.",
+      TYPE_COUNTER),
   FILES_COPIED("files_copied",
-      "Total number of files copied within the object store."),
+      "Total number of files copied within the object store.",
+      TYPE_COUNTER),
   FILES_COPIED_BYTES("files_copied_bytes",
-      "Total number of bytes copied within the object store."),
+      "Total number of bytes copied within the object store.",
+      TYPE_COUNTER),
   FILES_CREATED("files_created",
-      "Total number of files created through the object store."),
+      "Total number of files created through the object store.",
+      TYPE_COUNTER),
   FILES_DELETED("files_deleted",
-      "Total number of files deleted from the object store."),
+      "Total number of files deleted from the object store.",
+      TYPE_COUNTER),
   FILES_DELETE_REJECTED("files_delete_rejected",
-      "Total number of files whose delete request was rejected"),
+      "Total number of files whose delete request was rejected",
+      TYPE_COUNTER),
   FAKE_DIRECTORIES_CREATED("fake_directories_created",
-      "Total number of fake directory entries created in the object store."),
+      "Total number of fake directory entries created in the object store.",
+      TYPE_COUNTER),
   FAKE_DIRECTORIES_DELETED("fake_directories_deleted",
-      "Total number of fake directory deletes submitted to object store."),
-  IGNORED_ERRORS("ignored_errors", "Errors caught and ignored"),
-  INVOCATION_COPY_FROM_LOCAL_FILE(CommonStatisticNames.OP_COPY_FROM_LOCAL_FILE,
-      "Calls of copyFromLocalFile()"),
-  INVOCATION_CREATE(CommonStatisticNames.OP_CREATE,
-      "Calls of create()"),
-  INVOCATION_CREATE_NON_RECURSIVE(CommonStatisticNames.OP_CREATE_NON_RECURSIVE,
-      "Calls of createNonRecursive()"),
-  INVOCATION_DELETE(CommonStatisticNames.OP_DELETE,
-      "Calls of delete()"),
-  INVOCATION_EXISTS(CommonStatisticNames.OP_EXISTS,
-      "Calls of exists()"),
-  INVOCATION_GET_DELEGATION_TOKEN(CommonStatisticNames.OP_GET_DELEGATION_TOKEN,
-      "Calls of getDelegationToken()"),
-  INVOCATION_GET_FILE_CHECKSUM(CommonStatisticNames.OP_GET_FILE_CHECKSUM,
-      "Calls of getFileChecksum()"),
-  INVOCATION_GET_FILE_STATUS(CommonStatisticNames.OP_GET_FILE_STATUS,
-      "Calls of getFileStatus()"),
-  INVOCATION_GLOB_STATUS(CommonStatisticNames.OP_GLOB_STATUS,
-      "Calls of globStatus()"),
-  INVOCATION_IS_DIRECTORY(CommonStatisticNames.OP_IS_DIRECTORY,
-      "Calls of isDirectory()"),
-  INVOCATION_IS_FILE(CommonStatisticNames.OP_IS_FILE,
-      "Calls of isFile()"),
-  INVOCATION_LIST_FILES(CommonStatisticNames.OP_LIST_FILES,
-      "Calls of listFiles()"),
-  INVOCATION_LIST_LOCATED_STATUS(CommonStatisticNames.OP_LIST_LOCATED_STATUS,
-      "Calls of listLocatedStatus()"),
-  INVOCATION_LIST_STATUS(CommonStatisticNames.OP_LIST_STATUS,
-      "Calls of listStatus()"),
-  INVOCATION_MKDIRS(CommonStatisticNames.OP_MKDIRS,
-      "Calls of mkdirs()"),
-  INVOCATION_OPEN(CommonStatisticNames.OP_OPEN,
-      "Calls of open()"),
-  INVOCATION_RENAME(CommonStatisticNames.OP_RENAME,
-      "Calls of rename()"),
-  OBJECT_COPY_REQUESTS("object_copy_requests", "Object copy requests"),
-  OBJECT_DELETE_REQUESTS("object_delete_requests", "Object delete requests"),
-  OBJECT_DELETE_OBJECTS("object_delete_objects",
-      "Objects deleted in delete requests"),
-  OBJECT_LIST_REQUESTS("object_list_requests",
-      "Number of object listings made"),
-  OBJECT_CONTINUE_LIST_REQUESTS("object_continue_list_requests",
-      "Number of continued object listings made"),
-  OBJECT_METADATA_REQUESTS("object_metadata_requests",
-      "Number of requests for object metadata"),
-  OBJECT_MULTIPART_UPLOAD_INITIATED("object_multipart_initiated",
-      "Object multipart upload initiated"),
-  OBJECT_MULTIPART_UPLOAD_ABORTED("object_multipart_aborted",
-      "Object multipart upload aborted"),
-  OBJECT_PUT_REQUESTS("object_put_requests",
-      "Object put/multipart upload count"),
-  OBJECT_PUT_REQUESTS_COMPLETED("object_put_requests_completed",
-      "Object put/multipart upload completed count"),
-  OBJECT_PUT_REQUESTS_ACTIVE("object_put_requests_active",
-      "Current number of active put requests"),
-  OBJECT_PUT_BYTES("object_put_bytes", "number of bytes uploaded"),
-  OBJECT_PUT_BYTES_PENDING("object_put_bytes_pending",
-      "number of bytes queued for upload/being actively uploaded"),
-  OBJECT_SELECT_REQUESTS("object_select_requests",
-      "Count of S3 Select requests issued"),
-  STREAM_ABORTED("stream_aborted",
-      "Count of times the TCP stream was aborted"),
-  STREAM_BACKWARD_SEEK_OPERATIONS("stream_backward_seek_operations",
-      "Number of executed seek operations which went backwards in a stream"),
-  STREAM_CLOSED("stream_closed", "Count of times the TCP stream was closed"),
-  STREAM_CLOSE_OPERATIONS("stream_close_operations",
-      "Total count of times an attempt to close a data stream was made"),
-  STREAM_FORWARD_SEEK_OPERATIONS("stream_forward_seek_operations",
-      "Number of executed seek operations which went forward in a stream"),
-  STREAM_OPENED("stream_opened",
-      "Total count of times an input stream to object store was opened"),
-  STREAM_READ_EXCEPTIONS("stream_read_exceptions",
-      "Number of exceptions invoked on input streams"),
-  STREAM_READ_FULLY_OPERATIONS("stream_read_fully_operations",
-      "Count of readFully() operations in streams"),
-  STREAM_READ_OPERATIONS("stream_read_operations",
-      "Count of read() operations in streams"),
-  STREAM_READ_OPERATIONS_INCOMPLETE("stream_read_operations_incomplete",
-      "Count of incomplete read() operations in streams"),
-  STREAM_READ_VERSION_MISMATCHES("stream_read_version_mismatches",
-      "Count of version mismatches encountered while reading streams"),
-  STREAM_SEEK_BYTES_BACKWARDS("stream_bytes_backwards_on_seek",
-      "Count of bytes moved backwards during seek operations"),
-  STREAM_SEEK_BYTES_READ("stream_bytes_read",
-      "Count of bytes read during seek() in stream operations"),
-  STREAM_SEEK_BYTES_SKIPPED("stream_bytes_skipped_on_seek",
-      "Count of bytes skipped during forward seek operation"),
-  STREAM_SEEK_OPERATIONS("stream_seek_operations",
-      "Number of seek operations during stream IO."),
-  STREAM_CLOSE_BYTES_READ("stream_bytes_read_in_close",
-      "Count of bytes read when closing streams during seek operations."),
-  STREAM_ABORT_BYTES_DISCARDED("stream_bytes_discarded_in_abort",
-      "Count of bytes discarded by aborting the stream"),
-  STREAM_WRITE_FAILURES("stream_write_failures",
-      "Count of stream write failures reported"),
-  STREAM_WRITE_BLOCK_UPLOADS("stream_write_block_uploads",
-      "Count of block/partition uploads completed"),
-  STREAM_WRITE_BLOCK_UPLOADS_ACTIVE("stream_write_block_uploads_active",
-      "Count of block/partition uploads completed"),
-  STREAM_WRITE_BLOCK_UPLOADS_COMMITTED("stream_write_block_uploads_committed",
-      "Count of number of block uploads committed"),
-  STREAM_WRITE_BLOCK_UPLOADS_ABORTED("stream_write_block_uploads_aborted",
-      "Count of number of block uploads aborted"),
-
-  STREAM_WRITE_BLOCK_UPLOADS_PENDING("stream_write_block_uploads_pending",
-      "Gauge of block/partitions uploads queued to be written"),
-  STREAM_WRITE_BLOCK_UPLOADS_DATA_PENDING(
-      "stream_write_block_uploads_data_pending",
-      "Gauge of block/partitions data uploads queued to be written"),
-  STREAM_WRITE_TOTAL_TIME("stream_write_total_time",
-      "Count of total time taken for uploads to complete"),
-  STREAM_WRITE_TOTAL_DATA("stream_write_total_data",
-      "Count of total data uploaded in block output"),
-  STREAM_WRITE_QUEUE_DURATION("stream_write_queue_duration",
-      "Total queue duration of all block uploads"),
-
-  // S3guard committer stats
+      "Total number of fake directory deletes submitted to object store.",
+      TYPE_COUNTER),
+  IGNORED_ERRORS("ignored_errors", "Errors caught and ignored",
+      TYPE_COUNTER),
+  INVOCATION_COPY_FROM_LOCAL_FILE(
+      StoreStatisticNames.OP_COPY_FROM_LOCAL_FILE,
+      "Calls of copyFromLocalFile()",
+      TYPE_COUNTER),
+  INVOCATION_CREATE(
+      StoreStatisticNames.OP_CREATE,
+      "Calls of create()",
+      TYPE_COUNTER),
+  INVOCATION_CREATE_NON_RECURSIVE(
+      StoreStatisticNames.OP_CREATE_NON_RECURSIVE,
+      "Calls of createNonRecursive()",
+      TYPE_COUNTER),
+  INVOCATION_DELETE(
+      StoreStatisticNames.OP_DELETE,
+      "Calls of delete()",
+      TYPE_COUNTER),
+  INVOCATION_EXISTS(
+      StoreStatisticNames.OP_EXISTS,
+      "Calls of exists()",
+      TYPE_COUNTER),
+  INVOCATION_GET_DELEGATION_TOKEN(
+      StoreStatisticNames.OP_GET_DELEGATION_TOKEN,
+      "Calls of getDelegationToken()",
+      TYPE_COUNTER),
+  INVOCATION_GET_FILE_CHECKSUM(
+      StoreStatisticNames.OP_GET_FILE_CHECKSUM,
+      "Calls of getFileChecksum()",
+      TYPE_COUNTER),
+  INVOCATION_GET_FILE_STATUS(
+      StoreStatisticNames.OP_GET_FILE_STATUS,
+      "Calls of getFileStatus()",
+      TYPE_COUNTER),
+  INVOCATION_GLOB_STATUS(
+      StoreStatisticNames.OP_GLOB_STATUS,
+      "Calls of globStatus()",
+      TYPE_COUNTER),
+  INVOCATION_IS_DIRECTORY(
+      StoreStatisticNames.OP_IS_DIRECTORY,
+      "Calls of isDirectory()",
+      TYPE_COUNTER),
+  INVOCATION_IS_FILE(
+      StoreStatisticNames.OP_IS_FILE,
+      "Calls of isFile()",
+      TYPE_COUNTER),
+  INVOCATION_LIST_FILES(
+      StoreStatisticNames.OP_LIST_FILES,
+      "Calls of listFiles()",
+      TYPE_COUNTER),
+  INVOCATION_LIST_LOCATED_STATUS(
+      StoreStatisticNames.OP_LIST_LOCATED_STATUS,
+      "Calls of listLocatedStatus()",
+      TYPE_COUNTER),
+  INVOCATION_LIST_STATUS(
+      StoreStatisticNames.OP_LIST_STATUS,
+      "Calls of listStatus()",
+      TYPE_COUNTER),
+  INVOCATION_MKDIRS(
+      StoreStatisticNames.OP_MKDIRS,
+      "Calls of mkdirs()",
+      TYPE_COUNTER),
+  INVOCATION_OPEN(
+      StoreStatisticNames.OP_OPEN,
+      "Calls of open()",
+      TYPE_COUNTER),
+  INVOCATION_RENAME(
+      StoreStatisticNames.OP_RENAME,
+      "Calls of rename()",
+      TYPE_COUNTER),
+
+  /* Object IO */
+  OBJECT_COPY_REQUESTS(StoreStatisticNames.OBJECT_COPY_REQUESTS,
+      "Object copy requests",
+      TYPE_COUNTER),
+  OBJECT_DELETE_REQUEST(StoreStatisticNames.OBJECT_DELETE_REQUEST,
+      "Object delete requests",
+      TYPE_DURATION),
+  OBJECT_BULK_DELETE_REQUEST(StoreStatisticNames.OBJECT_BULK_DELETE_REQUEST,
+      "Object bulk delete requests",
+      TYPE_DURATION),
+  OBJECT_DELETE_OBJECTS(StoreStatisticNames.OBJECT_DELETE_OBJECTS,
+      "Objects deleted in delete requests",
+      TYPE_COUNTER),
+  OBJECT_LIST_REQUEST(StoreStatisticNames.OBJECT_LIST_REQUEST,
+      "Count of object listings made",
+      TYPE_DURATION),
+  OBJECT_CONTINUE_LIST_REQUESTS(
+      StoreStatisticNames.OBJECT_CONTINUE_LIST_REQUEST,
+      "Count of continued object listings made",
+      TYPE_DURATION),
+  OBJECT_METADATA_REQUESTS(
+      StoreStatisticNames.OBJECT_METADATA_REQUESTS,
+      "Count of requests for object metadata",
+      TYPE_COUNTER),
+  OBJECT_MULTIPART_UPLOAD_INITIATED(
+      StoreStatisticNames.OBJECT_MULTIPART_UPLOAD_INITIATED,
+      "Object multipart upload initiated",
+      TYPE_COUNTER),
+  OBJECT_MULTIPART_UPLOAD_ABORTED(
+      StoreStatisticNames.OBJECT_MULTIPART_UPLOAD_ABORTED,
+      "Object multipart upload aborted",
+      TYPE_COUNTER),
+  OBJECT_PUT_REQUESTS(
+      StoreStatisticNames.OBJECT_PUT_REQUEST,
+      "Object put/multipart upload count",
+      TYPE_COUNTER),
+  OBJECT_PUT_REQUESTS_COMPLETED(
+      StoreStatisticNames.OBJECT_PUT_REQUEST_COMPLETED,
+      "Object put/multipart upload completed count",
+      TYPE_COUNTER),
+  OBJECT_PUT_REQUESTS_ACTIVE(
+      StoreStatisticNames.OBJECT_PUT_REQUEST_ACTIVE,
+      "Current number of active put requests",
+      TYPE_GAUGE),
+  OBJECT_PUT_BYTES(
+      StoreStatisticNames.OBJECT_PUT_BYTES,
+      "number of bytes uploaded",
+      TYPE_COUNTER),
+  OBJECT_PUT_BYTES_PENDING(
+      StoreStatisticNames.OBJECT_PUT_BYTES_PENDING,
+      "number of bytes queued for upload/being actively uploaded",
+      TYPE_GAUGE),
+  OBJECT_SELECT_REQUESTS(
+      StoreStatisticNames.OBJECT_SELECT_REQUESTS,
+      "Count of S3 Select requests issued",
+      TYPE_COUNTER),
+  STREAM_READ_ABORTED(
+      StreamStatisticNames.STREAM_READ_ABORTED,
+      "Count of times the TCP stream was aborted",
+      TYPE_COUNTER),
+
+  /* Stream Reads */
+  STREAM_READ_BYTES(
+      StreamStatisticNames.STREAM_READ_BYTES,
+      "Bytes read from an input stream in read() calls",
+      TYPE_COUNTER),
+  STREAM_READ_BYTES_DISCARDED_ABORT(
+      StreamStatisticNames.STREAM_READ_BYTES_DISCARDED_ABORT,
+      "Count of bytes discarded by aborting an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_BYTES_READ_CLOSE(
+      StreamStatisticNames.STREAM_READ_BYTES_DISCARDED_CLOSE,
+      "Count of bytes read and discarded when closing an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_CLOSED(
+      StreamStatisticNames.STREAM_READ_CLOSED,
+      "Count of times the TCP stream was closed",
+      TYPE_COUNTER),
+  STREAM_READ_CLOSE_OPERATIONS(
+      StreamStatisticNames.STREAM_READ_CLOSE_OPERATIONS,
+      "Total count of times an attempt to close an input stream was made",
+      TYPE_COUNTER),
+  STREAM_READ_EXCEPTIONS(
+      StreamStatisticNames.STREAM_READ_EXCEPTIONS,
+      "Count of exceptions raised during input stream reads",
+      TYPE_COUNTER),
+  STREAM_READ_FULLY_OPERATIONS(
+      StreamStatisticNames.STREAM_READ_FULLY_OPERATIONS,
+      "Count of readFully() operations in an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_OPENED(
+      StreamStatisticNames.STREAM_READ_OPENED,
+      "Total count of times an input stream to object store data was opened",
+      TYPE_COUNTER),
+  STREAM_READ_OPERATIONS(
+      StreamStatisticNames.STREAM_READ_OPERATIONS,
+      "Count of read() operations in an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_OPERATIONS_INCOMPLETE(
+      StreamStatisticNames.STREAM_READ_OPERATIONS_INCOMPLETE,
+      "Count of incomplete read() operations in an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_VERSION_MISMATCHES(
+      StreamStatisticNames.STREAM_READ_VERSION_MISMATCHES,
+      "Count of version mismatches encountered while reading an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_SEEK_BACKWARD_OPERATIONS(
+      StreamStatisticNames.STREAM_READ_SEEK_BACKWARD_OPERATIONS,
+      "Count of executed seek operations which went backwards in a stream",
+      TYPE_COUNTER),
+  STREAM_READ_SEEK_BYTES_BACKWARDS(
+      StreamStatisticNames.STREAM_READ_SEEK_BYTES_BACKWARDS,
+      "Count of bytes moved backwards during seek operations"
+          + " in an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_SEEK_BYTES_DISCARDED(
+      StreamStatisticNames.STREAM_READ_SEEK_BYTES_DISCARDED,
+      "Count of bytes read and discarded during seek() in an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_SEEK_BYTES_SKIPPED(
+      StreamStatisticNames.STREAM_READ_SEEK_BYTES_SKIPPED,
+      "Count of bytes skipped during forward seek operations"
+          + " an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_SEEK_FORWARD_OPERATIONS(
+      StreamStatisticNames.STREAM_READ_SEEK_FORWARD_OPERATIONS,
+      "Count of executed seek operations which went forward in"
+          + " an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_SEEK_OPERATIONS(
+      StreamStatisticNames.STREAM_READ_SEEK_OPERATIONS,
+      "Count of seek operations in an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_SEEK_POLICY_CHANGED(
+      StreamStatisticNames.STREAM_READ_SEEK_POLICY_CHANGED,
+      "Count of times the seek policy was dynamically changed"
+          + " in an input stream",
+      TYPE_COUNTER),
+  STREAM_READ_TOTAL_BYTES(
+      StreamStatisticNames.STREAM_READ_TOTAL_BYTES,
+      "Total count of bytes read from an input stream",
+      TYPE_COUNTER),
+
+  /* Stream Write statistics */
+
+  STREAM_WRITE_EXCEPTIONS(
+      StreamStatisticNames.STREAM_WRITE_EXCEPTIONS,
+      "Count of stream write failures reported",
+      TYPE_COUNTER),
+  STREAM_WRITE_EXCEPTIONS_COMPLETING_UPLOADS(
+      StreamStatisticNames.STREAM_WRITE_EXCEPTIONS_COMPLETING_UPLOADS,
+      "Count of failures when finalizing a multipart upload",
+      TYPE_COUNTER),
+  STREAM_WRITE_BLOCK_UPLOADS(
+      StreamStatisticNames.STREAM_WRITE_BLOCK_UPLOADS,
+      "Count of block/partition uploads completed",
+      TYPE_COUNTER),
+  STREAM_WRITE_BLOCK_UPLOADS_ACTIVE(
+      StreamStatisticNames.STREAM_WRITE_BLOCK_UPLOADS_ACTIVE,
+      "Count of block/partition uploads active",
+      TYPE_GAUGE),
+  STREAM_WRITE_BLOCK_UPLOADS_COMMITTED(
+      StreamStatisticNames.STREAM_WRITE_BLOCK_UPLOADS_COMMITTED,
+      "Count of number of block uploads committed",
+      TYPE_COUNTER),
+  STREAM_WRITE_BLOCK_UPLOADS_ABORTED(
+      StreamStatisticNames.STREAM_WRITE_BLOCK_UPLOADS_ABORTED,
+      "Count of number of block uploads aborted",
+      TYPE_COUNTER),
+
+  STREAM_WRITE_BLOCK_UPLOADS_PENDING(
+      StreamStatisticNames.STREAM_WRITE_BLOCK_UPLOADS_PENDING,
+      "Gauge of block/partitions uploads queued to be written",
+      TYPE_GAUGE),
+  STREAM_WRITE_BLOCK_UPLOADS_BYTES_PENDING(
+      StreamStatisticNames.STREAM_WRITE_BLOCK_UPLOADS_BYTES_PENDING,
+      "Gauge of data queued to be written",
+      TYPE_GAUGE),
+  STREAM_WRITE_TOTAL_TIME(
+      StreamStatisticNames.STREAM_WRITE_TOTAL_TIME,
+      "Count of total time taken for uploads to complete",
+      TYPE_COUNTER),
+  STREAM_WRITE_TOTAL_DATA(StreamStatisticNames.STREAM_WRITE_TOTAL_DATA,
+      "Count of total data uploaded",
+      TYPE_COUNTER),
+  STREAM_WRITE_BYTES(
+      StreamStatisticNames.STREAM_WRITE_BYTES,
+      "Count of bytes written to output stream"
+          + " (including all not yet uploaded)",
+      TYPE_COUNTER),
+  STREAM_WRITE_QUEUE_DURATION(
+      StreamStatisticNames.STREAM_WRITE_QUEUE_DURATION,
+      "Total queue duration of all block uploads",
+      TYPE_DURATION),
+
+  /* committer stats */
   COMMITTER_COMMITS_CREATED(
       "committer_commits_created",
-      "Number of files to commit created"),
+      "Count of files to commit created",
+      TYPE_COUNTER),
   COMMITTER_COMMITS_COMPLETED(
       "committer_commits_completed",
-      "Number of files committed"),
+      "Count of files committed",
+      TYPE_COUNTER),
+  COMMITTER_COMMIT_JOB(
+      "committer_commit_job",
+      "Duration Tracking of time to commit an entire job",
+      TYPE_DURATION),
   COMMITTER_JOBS_SUCCEEDED(
       "committer_jobs_completed",
-      "Number of successful jobs"),
+      "Count of successful jobs",
+      TYPE_COUNTER),
   COMMITTER_JOBS_FAILED(
       "committer_jobs_failed",
-      "Number of failed jobs"),
+      "Count of failed jobs",
+      TYPE_COUNTER),
   COMMITTER_TASKS_SUCCEEDED(
       "committer_tasks_completed",
-      "Number of successful tasks"),
+      "Count of successful tasks",
+      TYPE_COUNTER),
   COMMITTER_TASKS_FAILED(
       "committer_tasks_failed",
-      "Number of failed tasks"),
+      "Count of failed tasks",
+      TYPE_COUNTER),
   COMMITTER_BYTES_COMMITTED(
       "committer_bytes_committed",
-      "Amount of data committed"),
+      "Amount of data committed",
+      TYPE_COUNTER),
   COMMITTER_BYTES_UPLOADED(
       "committer_bytes_uploaded",
-      "Number of bytes uploaded duing commit operations"),
+      "Count of bytes uploaded duing commit operations",
+      TYPE_COUNTER),
   COMMITTER_COMMITS_FAILED(
-      "committer_commits_failed",
-      "Number of commits failed"),
+      "committer_commits"+ StoreStatisticNames.SUFFIX_FAILURES,
+      "Count of commits failed",
+      TYPE_COUNTER),
   COMMITTER_COMMITS_ABORTED(
       "committer_commits_aborted",
-      "Number of commits aborted"),
+      "Count of commits aborted",
+      TYPE_COUNTER),
   COMMITTER_COMMITS_REVERTED(
       "committer_commits_reverted",
-      "Number of commits reverted"),
+      "Count of commits reverted",
+      TYPE_COUNTER),
   COMMITTER_MAGIC_FILES_CREATED(
       "committer_magic_files_created",
-      "Number of files created under 'magic' paths"),
+      "Count of files created under 'magic' paths",
+      TYPE_COUNTER),
+  COMMITTER_MATERIALIZE_FILE(
+      "committer_materialize_file",
+      "Duration Tracking of time to materialize a file in job commit",
+      TYPE_DURATION),
+  COMMITTER_STAGE_FILE_UPLOAD(
+      "committer_stage_file_upload",
+      "Duration Tracking of files uploaded from a local staging path",
+      TYPE_DURATION),
 
-  // S3guard stats
+  /* S3guard stats */
   S3GUARD_METADATASTORE_PUT_PATH_REQUEST(
       "s3guard_metadatastore_put_path_request",
-      "S3Guard metadata store put one metadata path request"),
+      "S3Guard metadata store put one metadata path request",
+      TYPE_COUNTER),
   S3GUARD_METADATASTORE_PUT_PATH_LATENCY(
       "s3guard_metadatastore_put_path_latency",
-      "S3Guard metadata store put one metadata path latency"),
-  S3GUARD_METADATASTORE_INITIALIZATION("s3guard_metadatastore_initialization",
-      "S3Guard metadata store initialization times"),
+      "S3Guard metadata store put one metadata path latency",
+      TYPE_QUANTILE),
+  S3GUARD_METADATASTORE_INITIALIZATION(
+      "s3guard_metadatastore_initialization",
+      "S3Guard metadata store initialization times",
+      TYPE_COUNTER),
   S3GUARD_METADATASTORE_RECORD_DELETES(
       "s3guard_metadatastore_record_deletes",
-      "S3Guard metadata store records deleted"),
+      "S3Guard metadata store records deleted",
+      TYPE_COUNTER),
   S3GUARD_METADATASTORE_RECORD_READS(
       "s3guard_metadatastore_record_reads",
-      "S3Guard metadata store records read"),
+      "S3Guard metadata store records read",
+      TYPE_COUNTER),
   S3GUARD_METADATASTORE_RECORD_WRITES(
       "s3guard_metadatastore_record_writes",
-      "S3Guard metadata store records written"),
+      "S3Guard metadata store records written",
+      TYPE_COUNTER),
   S3GUARD_METADATASTORE_RETRY("s3guard_metadatastore_retry",
-      "S3Guard metadata store retry events"),
+      "S3Guard metadata store retry events",
+      TYPE_COUNTER),
   S3GUARD_METADATASTORE_THROTTLED("s3guard_metadatastore_throttled",
-      "S3Guard metadata store throttled events"),
+      "S3Guard metadata store throttled events",
+      TYPE_COUNTER),
   S3GUARD_METADATASTORE_THROTTLE_RATE(
       "s3guard_metadatastore_throttle_rate",
-      "S3Guard metadata store throttle rate"),
+      "S3Guard metadata store throttle rate",
+      TYPE_QUANTILE),
   S3GUARD_METADATASTORE_AUTHORITATIVE_DIRECTORIES_UPDATED(
       "s3guard_metadatastore_authoritative_directories_updated",
-      "S3Guard metadata store authoritative directories updated from S3"),
-
-  STORE_IO_THROTTLED("store_io_throttled", "Requests throttled and retried"),
-  STORE_IO_THROTTLE_RATE("store_io_throttle_rate",
-      "Rate of S3 request throttling"),
-
-  DELEGATION_TOKENS_ISSUED("delegation_tokens_issued",
-      "Number of delegation tokens issued"),
-
-  MULTIPART_INSTANTIATED(
-      "multipart_instantiated",
-      "Multipart Uploader Instantiated"),
-  MULTIPART_PART_PUT(
-      "multipart_part_put",
-      "Multipart Part Put Operation"),
-  MULTIPART_PART_PUT_BYTES(
-      "multipart_part_put_bytes",
-      "Multipart Part Put Bytes"),
+      "S3Guard metadata store authoritative directories updated from S3",
+      TYPE_COUNTER),
+
+
+  /* General Store operations */
+  STORE_IO_REQUEST(StoreStatisticNames.STORE_IO_REQUEST,
+      "requests made of the remote store",
+      TYPE_COUNTER),
+
+  STORE_IO_RETRY(StoreStatisticNames.STORE_IO_RETRY,
+      "retried requests made of the remote store",
+      TYPE_COUNTER),
+
+  STORE_IO_THROTTLED(
+      StoreStatisticNames.STORE_IO_THROTTLED,
+      "Requests throttled and retried",
+      TYPE_COUNTER),
+  STORE_IO_THROTTLE_RATE(
+      StoreStatisticNames.STORE_IO_THROTTLE_RATE,
+      "Rate of S3 request throttling",
+      TYPE_QUANTILE),
+
+  /*
+   * Delegation Token Operations.
+   */
+  DELEGATION_TOKEN_ISSUED(
+      StoreStatisticNames.DELEGATION_TOKEN_ISSUED,
+      "Count of delegation tokens issued",
+      TYPE_DURATION),
+
+  /* Multipart Upload API */
+
+  MULTIPART_UPLOAD_INSTANTIATED(
+      StoreStatisticNames.MULTIPART_UPLOAD_INSTANTIATED,
+      "Multipart Uploader Instantiated",
+      TYPE_COUNTER),
+  MULTIPART_UPLOAD_PART_PUT(
+      StoreStatisticNames.MULTIPART_UPLOAD_PART_PUT,
+      "Multipart Part Put Operation",
+      TYPE_COUNTER),
+  MULTIPART_UPLOAD_PART_PUT_BYTES(
+      StoreStatisticNames.MULTIPART_UPLOAD_PART_PUT_BYTES,
+      "Multipart Part Put Bytes",
+      TYPE_COUNTER),
   MULTIPART_UPLOAD_ABORTED(
-      "multipart_upload_aborted",
-      "Multipart Upload Aborted"),
+      StoreStatisticNames.MULTIPART_UPLOAD_ABORTED,
+      "Multipart Upload Aborted",
+      TYPE_COUNTER),
   MULTIPART_UPLOAD_ABORT_UNDER_PATH_INVOKED(
-      "multipart_upload_abort_under_path_invoked",
-      "Multipart Upload Abort Udner Path Invoked"),
+      StoreStatisticNames.MULTIPART_UPLOAD_ABORT_UNDER_PATH_INVOKED,
+      "Multipart Upload Abort Unner Path Invoked",
+      TYPE_COUNTER),
   MULTIPART_UPLOAD_COMPLETED(
-      "multipart_upload_completed",
-      "Multipart Upload Completed"),
+      StoreStatisticNames.MULTIPART_UPLOAD_COMPLETED,
+      "Multipart Upload Completed",
+      TYPE_COUNTER),
   MULTIPART_UPLOAD_STARTED(
-      "multipart_upload_started",
-      "Multipart Upload Started");
+      StoreStatisticNames.MULTIPART_UPLOAD_STARTED,
+      "Multipart Upload Started",
+      TYPE_COUNTER);
+
 
+  /**
+   * A map used to support the {@link #fromSymbol(String)} call.
+   */
   private static final Map<String, Statistic> SYMBOL_MAP =
       new HashMap<>(Statistic.values().length);
   static {
@@ -268,14 +524,28 @@ public enum Statistic {
     }
   }
 
-  Statistic(String symbol, String description) {
+
+  /**
+   * Statistic definition.
+   * @param symbol name
+   * @param description description.
+   * @param type type
+   */
+  Statistic(String symbol, String description, StatisticTypeEnum type) {
     this.symbol = symbol;
     this.description = description;
+    this.type = type;
   }
 
+  /** Statistic name. */
   private final String symbol;
+
+  /** Statistic description. */
   private final String description;
 
+  /** Statistic type. */
+  private final StatisticTypeEnum type;
+
   public String getSymbol() {
     return symbol;
   }
@@ -302,4 +572,12 @@ public enum Statistic {
   public String toString() {
     return symbol;
   }
+
+  /**
+   * What type is this statistic?
+   * @return the type.
+   */
+  public StatisticTypeEnum getType() {
+    return type;
+  }
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/WriteOperationHelper.java

@@ -50,10 +50,12 @@ import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.PathIOException;
+import org.apache.hadoop.fs.s3a.statistics.S3AStatisticsContext;
 import org.apache.hadoop.fs.s3a.s3guard.BulkOperationState;
 import org.apache.hadoop.fs.s3a.s3guard.S3Guard;
 import org.apache.hadoop.fs.s3a.select.SelectBinding;
 import org.apache.hadoop.util.DurationInfo;
+import org.apache.hadoop.util.functional.CallableRaisingIOE;
 
 import static org.apache.hadoop.thirdparty.com.google.common.base.Preconditions.checkArgument;
 import static org.apache.hadoop.thirdparty.com.google.common.base.Preconditions.checkNotNull;
@@ -108,17 +110,26 @@ public class WriteOperationHelper implements WriteOperations {
   /** Bucket of the owner FS. */
   private final String bucket;
 
+  /**
+   * statistics context.
+   */
+  private final S3AStatisticsContext statisticsContext;
+
   /**
    * Constructor.
    * @param owner owner FS creating the helper
    * @param conf Configuration object
+   * @param statisticsContext statistics context
    *
    */
-  protected WriteOperationHelper(S3AFileSystem owner, Configuration conf) {
+  protected WriteOperationHelper(S3AFileSystem owner,
+      Configuration conf,
+      S3AStatisticsContext statisticsContext) {
     this.owner = owner;
     this.invoker = new Invoker(new S3ARetryPolicy(conf),
         this::operationRetried);
     this.conf = conf;
+    this.statisticsContext = statisticsContext;
     bucket = owner.getBucket();
   }
 
@@ -138,19 +149,19 @@ public class WriteOperationHelper implements WriteOperations {
 
   /**
    * Execute a function with retry processing.
+   * @param <T> type of return value
    * @param action action to execute (used in error messages)
    * @param path path of work (used in error messages)
    * @param idempotent does the operation have semantics
    * which mean that it can be retried even if was already executed?
    * @param operation operation to execute
-   * @param <T> type of return value
    * @return the result of the call
    * @throws IOException any IOE raised, or translated exception
    */
   public <T> T retry(String action,
       String path,
       boolean idempotent,
-      Invoker.Operation<T> operation)
+      CallableRaisingIOE<T> operation)
       throws IOException {
 
     return invoker.retry(action, path, idempotent, operation);

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/WriteOperations.java

@@ -42,6 +42,7 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.PathIOException;
 import org.apache.hadoop.fs.s3a.s3guard.BulkOperationState;
+import org.apache.hadoop.util.functional.CallableRaisingIOE;
 
 /**
  * Operations to update the store.
@@ -56,19 +57,19 @@ public interface WriteOperations {
 
   /**
    * Execute a function with retry processing.
+   * @param <T> type of return value
    * @param action action to execute (used in error messages)
    * @param path path of work (used in error messages)
    * @param idempotent does the operation have semantics
    * which mean that it can be retried even if was already executed?
    * @param operation operation to execute
-   * @param <T> type of return value
    * @return the result of the call
    * @throws IOException any IOE raised, or translated exception
    */
   <T> T retry(String action,
       String path,
       boolean idempotent,
-      Invoker.Operation<T> operation)
+      CallableRaisingIOE<T> operation)
       throws IOException;
 
   /**

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/auth/delegation/S3ADelegationTokens.java

@@ -34,9 +34,9 @@ import org.apache.commons.lang3.StringUtils;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.s3a.AWSCredentialProviderList;
-import org.apache.hadoop.fs.s3a.S3AInstrumentation;
 import org.apache.hadoop.fs.s3a.auth.RoleModel;
 import org.apache.hadoop.fs.s3a.impl.StoreContext;
+import org.apache.hadoop.fs.s3a.statistics.DelegationTokenStatistics;
 import org.apache.hadoop.io.Text;
 import org.apache.hadoop.security.Credentials;
 import org.apache.hadoop.security.UserGroupInformation;
@@ -45,6 +45,8 @@ import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.service.ServiceOperations;
 import org.apache.hadoop.util.DurationInfo;
 
+import static org.apache.hadoop.fs.s3a.Statistic.DELEGATION_TOKEN_ISSUED;
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.trackDuration;
 import static org.apache.hadoop.thirdparty.com.google.common.base.Preconditions.checkArgument;
 import static org.apache.hadoop.thirdparty.com.google.common.base.Preconditions.checkState;
 import static org.apache.hadoop.fs.s3a.auth.delegation.DelegationConstants.DEFAULT_DELEGATION_TOKEN_BINDING;
@@ -135,9 +137,9 @@ public class S3ADelegationTokens extends AbstractDTService {
           AWSPolicyProvider.AccessLevel.WRITE);
 
   /**
-   * Statistics for the owner FS.
+   * Statistics for the operations.
    */
-  private S3AInstrumentation.DelegationTokenStatistics stats;
+  private DelegationTokenStatistics stats;
 
   /**
    * Name of the token binding as extracted from token kind; used for
@@ -428,8 +430,10 @@ public class S3ADelegationTokens extends AbstractDTService {
 
     try(DurationInfo ignored = new DurationInfo(LOG, DURATION_LOG_AT_INFO,
         "Creating New Delegation Token", tokenBinding.getKind())) {
-      Token<AbstractS3ATokenIdentifier> token
-          = tokenBinding.createDelegationToken(rolePolicy, encryptionSecrets, renewer);
+      Token<AbstractS3ATokenIdentifier> token = trackDuration(stats,
+          DELEGATION_TOKEN_ISSUED.getSymbol(), () ->
+              tokenBinding.createDelegationToken(rolePolicy,
+                  encryptionSecrets, renewer));
       if (token != null) {
         token.setService(service);
         noteTokenCreated(token);

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/commit/AbstractS3ACommitter.java

@@ -47,6 +47,10 @@ import org.apache.hadoop.fs.s3a.S3AFileSystem;
 import org.apache.hadoop.fs.s3a.commit.files.PendingSet;
 import org.apache.hadoop.fs.s3a.commit.files.SinglePendingCommit;
 import org.apache.hadoop.fs.s3a.commit.files.SuccessData;
+import org.apache.hadoop.fs.s3a.statistics.CommitterStatistics;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.fs.statistics.IOStatisticsSnapshot;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
 import org.apache.hadoop.mapreduce.JobContext;
 import org.apache.hadoop.mapreduce.JobID;
 import org.apache.hadoop.mapreduce.JobStatus;
@@ -60,6 +64,7 @@ import org.apache.hadoop.util.concurrent.HadoopExecutors;
 import static org.apache.hadoop.fs.s3a.Constants.THREAD_POOL_SHUTDOWN_DELAY_SECONDS;
 import static org.apache.hadoop.fs.s3a.Invoker.ignoreIOExceptions;
 import static org.apache.hadoop.fs.s3a.S3AUtils.*;
+import static org.apache.hadoop.fs.s3a.Statistic.COMMITTER_COMMIT_JOB;
 import static org.apache.hadoop.fs.s3a.commit.CommitConstants.*;
 import static org.apache.hadoop.fs.s3a.commit.CommitUtils.*;
 import static org.apache.hadoop.fs.s3a.commit.CommitUtilsWithMR.*;
@@ -67,6 +72,7 @@ import static org.apache.hadoop.fs.s3a.commit.InternalCommitterConstants.E_NO_SP
 import static org.apache.hadoop.fs.s3a.commit.InternalCommitterConstants.FS_S3A_COMMITTER_UUID;
 import static org.apache.hadoop.fs.s3a.commit.InternalCommitterConstants.FS_S3A_COMMITTER_UUID_SOURCE;
 import static org.apache.hadoop.fs.s3a.commit.InternalCommitterConstants.SPARK_WRITE_UUID;
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.trackDurationOfInvocation;
 
 /**
  * Abstract base class for S3A committers; allows for any commonality
@@ -94,7 +100,8 @@ import static org.apache.hadoop.fs.s3a.commit.InternalCommitterConstants.SPARK_W
  * created by a few tasks, <i>and</i> the HTTP connection pool in the S3A
  * committer was large enough for more all the parallel POST requests.
  */
-public abstract class AbstractS3ACommitter extends PathOutputCommitter {
+public abstract class AbstractS3ACommitter extends PathOutputCommitter
+    implements IOStatisticsSource {
 
   private static final Logger LOG =
       LoggerFactory.getLogger(AbstractS3ACommitter.class);
@@ -166,6 +173,8 @@ public abstract class AbstractS3ACommitter extends PathOutputCommitter {
   /** Should a job marker be created? */
   private final boolean createJobMarker;
 
+  private final CommitterStatistics committerStatistics;
+
   /**
    * Create a committer.
    * This constructor binds the destination directory and configuration, but
@@ -197,7 +206,9 @@ public abstract class AbstractS3ACommitter extends PathOutputCommitter {
     this.createJobMarker = context.getConfiguration().getBoolean(
         CREATE_SUCCESSFUL_JOB_OUTPUT_DIR_MARKER,
         DEFAULT_CREATE_SUCCESSFUL_JOB_DIR_MARKER);
-    this.commitOperations = new CommitOperations(fs);
+    // the statistics are shared between this committer and its operations.
+    this.committerStatistics = fs.newCommitterStatistics();
+    this.commitOperations = new CommitOperations(fs, committerStatistics);
   }
 
   /**
@@ -437,7 +448,12 @@ public abstract class AbstractS3ACommitter extends PathOutputCommitter {
     // The list of committed objects in pending is size limited in
     // ActiveCommit.uploadCommitted.
     filenames.addAll(pending.committedObjects);
-    maybeCreateSuccessMarker(context, filenames);
+    // load in all the pending statistics
+    IOStatisticsSnapshot snapshot = new IOStatisticsSnapshot(
+        pending.getIOStatistics());
+    snapshot.aggregate(getIOStatistics());
+
+    maybeCreateSuccessMarker(context, filenames, snapshot);
   }
 
   /**
@@ -448,10 +464,12 @@ public abstract class AbstractS3ACommitter extends PathOutputCommitter {
    * PUT up a the contents of a {@link SuccessData} file.
    * @param context job context
    * @param filenames list of filenames.
+   * @param ioStatistics any IO Statistics to include
    * @throws IOException IO failure
    */
   protected void maybeCreateSuccessMarker(JobContext context,
-      List<String> filenames)
+      List<String> filenames,
+      final IOStatisticsSnapshot ioStatistics)
       throws IOException {
     if (createJobMarker) {
       // create a success data structure and then save it
@@ -465,6 +483,7 @@ public abstract class AbstractS3ACommitter extends PathOutputCommitter {
       successData.setTimestamp(now.getTime());
       successData.setDate(now.toString());
       successData.setFilenames(filenames);
+      successData.getIOStatistics().aggregate(ioStatistics);
       commitOperations.createSuccessMarker(getOutputPath(), successData, true);
     }
   }
@@ -644,6 +663,7 @@ public abstract class AbstractS3ACommitter extends PathOutputCommitter {
             activeCommit.uploadCommitted(
                 commit.getDestinationKey(), commit.getLength());
           });
+      activeCommit.pendingsetCommitted(pendingSet.getIOStatistics());
     }
   }
 
@@ -728,8 +748,9 @@ public abstract class AbstractS3ACommitter extends PathOutputCommitter {
   protected void commitJobInternal(JobContext context,
       ActiveCommit pending)
       throws IOException {
-
-    commitPendingUploads(context, pending);
+    trackDurationOfInvocation(committerStatistics,
+        COMMITTER_COMMIT_JOB.getSymbol(),
+        () -> commitPendingUploads(context, pending));
   }
 
   @Override
@@ -1175,6 +1196,11 @@ public abstract class AbstractS3ACommitter extends PathOutputCommitter {
     }
   }
 
+  @Override
+  public IOStatistics getIOStatistics() {
+    return committerStatistics.getIOStatistics();
+  }
+
   /**
    * Scan for active uploads and list them along with a warning message.
    * Errors are ignored.
@@ -1385,6 +1411,13 @@ public abstract class AbstractS3ACommitter extends PathOutputCommitter {
      */
     private long committedBytes;
 
+    /**
+     * Aggregate statistics of all supplied by
+     * committed uploads.
+     */
+    private final IOStatisticsSnapshot ioStatistics =
+        new IOStatisticsSnapshot();
+
     /**
      * Construct from a source FS and list of files.
      * @param sourceFS filesystem containing the list of pending files
@@ -1433,7 +1466,8 @@ public abstract class AbstractS3ACommitter extends PathOutputCommitter {
      * @param key key of the committed object.
      * @param size size in bytes.
      */
-    public synchronized void uploadCommitted(String key, long size) {
+    public synchronized void uploadCommitted(String key,
+        long size) {
       if (committedObjects.size() < SUCCESS_MARKER_FILE_LIMIT) {
         committedObjects.add(
             key.startsWith("/") ? key : ("/" + key));
@@ -1442,6 +1476,19 @@ public abstract class AbstractS3ACommitter extends PathOutputCommitter {
       committedBytes += size;
     }
 
+    /**
+     * Callback when a pendingset has been committed,
+     * including any source statistics.
+     * @param sourceStatistics any source statistics
+     */
+    public void pendingsetCommitted(final IOStatistics sourceStatistics) {
+      ioStatistics.aggregate(sourceStatistics);
+    }
+
+    public IOStatisticsSnapshot getIOStatistics() {
+      return ioStatistics;
+    }
+
     public synchronized List<String> getCommittedObjects() {
       return committedObjects;
     }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/commit/CommitOperations.java

@@ -45,7 +45,6 @@ import org.apache.hadoop.fs.PathFilter;
 import org.apache.hadoop.fs.PathIOException;
 import org.apache.hadoop.fs.RemoteIterator;
 import org.apache.hadoop.fs.s3a.S3AFileSystem;
-import org.apache.hadoop.fs.s3a.S3AInstrumentation;
 import org.apache.hadoop.fs.s3a.S3AUtils;
 import org.apache.hadoop.fs.s3a.WriteOperationHelper;
 import org.apache.hadoop.fs.s3a.commit.files.PendingSet;
@@ -53,13 +52,21 @@ import org.apache.hadoop.fs.s3a.commit.files.SinglePendingCommit;
 import org.apache.hadoop.fs.s3a.commit.files.SuccessData;
 import org.apache.hadoop.fs.s3a.impl.InternalConstants;
 import org.apache.hadoop.fs.s3a.s3guard.BulkOperationState;
+import org.apache.hadoop.fs.s3a.statistics.CommitterStatistics;
+import org.apache.hadoop.fs.statistics.DurationTracker;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.util.DurationInfo;
 import org.apache.hadoop.util.Progressable;
 
+import static java.util.Objects.requireNonNull;
 import static org.apache.hadoop.fs.s3a.S3AUtils.*;
+import static org.apache.hadoop.fs.s3a.Statistic.COMMITTER_MATERIALIZE_FILE;
+import static org.apache.hadoop.fs.s3a.Statistic.COMMITTER_STAGE_FILE_UPLOAD;
 import static org.apache.hadoop.fs.s3a.commit.CommitConstants.*;
 import static org.apache.hadoop.fs.s3a.Constants.*;
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.trackDuration;
 
 /**
  * The implementation of the various actions a committer needs.
@@ -71,7 +78,7 @@ import static org.apache.hadoop.fs.s3a.Constants.*;
  * duplicate that work.
  *
  */
-public class CommitOperations {
+public class CommitOperations implements IOStatisticsSource {
   private static final Logger LOG = LoggerFactory.getLogger(
       CommitOperations.class);
 
@@ -81,7 +88,7 @@ public class CommitOperations {
   private final S3AFileSystem fs;
 
   /** Statistics. */
-  private final S3AInstrumentation.CommitterStatistics statistics;
+  private final CommitterStatistics statistics;
 
   /**
    * Write operations for the destination fs.
@@ -105,9 +112,18 @@ public class CommitOperations {
    * @param fs FS to bind to
    */
   public CommitOperations(S3AFileSystem fs) {
-    Preconditions.checkArgument(fs != null, "null fs");
-    this.fs = fs;
-    statistics = fs.newCommitterStatistics();
+    this(requireNonNull(fs), fs.newCommitterStatistics());
+  }
+
+  /**
+   * Instantiate.
+   * @param fs FS to bind to
+   * @param committerStatistics committer statistics
+   */
+  public CommitOperations(S3AFileSystem fs,
+      CommitterStatistics committerStatistics) {
+    this.fs = requireNonNull(fs);
+    statistics = requireNonNull(committerStatistics);
     writeOperations = fs.getWriteOperationHelper();
   }
 
@@ -128,10 +144,15 @@ public class CommitOperations {
   }
 
   /** @return statistics. */
-  protected S3AInstrumentation.CommitterStatistics getStatistics() {
+  protected CommitterStatistics getStatistics() {
     return statistics;
   }
 
+  @Override
+  public IOStatistics getIOStatistics() {
+    return statistics.getIOStatistics();
+  }
+
   /**
    * Commit the operation, throwing an exception on any failure.
    * @param commit commit to execute
@@ -166,7 +187,8 @@ public class CommitOperations {
 
       commit.validate();
       destKey = commit.getDestinationKey();
-      long l = innerCommit(commit, operationState);
+      long l = trackDuration(statistics, COMMITTER_MATERIALIZE_FILE.getSymbol(),
+          () -> innerCommit(commit, operationState));
       LOG.debug("Successful commit of file length {}", l);
       outcome = MaybeIOE.NONE;
       statistics.commitCompleted(commit.getLength());
@@ -449,7 +471,7 @@ public class CommitOperations {
    * @return a pending upload entry
    * @throws IOException failure
    */
-  public SinglePendingCommit uploadFileToPendingCommit(File localFile,
+  public SinglePendingCommit  uploadFileToPendingCommit(File localFile,
       Path destPath,
       String partition,
       long uploadPartSize,
@@ -466,7 +488,11 @@ public class CommitOperations {
     String destKey = fs.pathToKey(destPath);
     String uploadId = null;
 
+    // flag to indicate to the finally clause that the operation
+    // failed. it is cleared as the last action in the try block.
     boolean threw = true;
+    final DurationTracker tracker = statistics.trackDuration(
+        COMMITTER_STAGE_FILE_UPLOAD.getSymbol());
     try (DurationInfo d = new DurationInfo(LOG,
         "Upload staged file from %s to %s",
         localFile.getAbsolutePath(),
@@ -507,6 +533,7 @@ public class CommitOperations {
       LOG.debug("File size is {}, number of parts to upload = {}",
           length, numParts);
       for (int partNumber = 1; partNumber <= numParts; partNumber += 1) {
+        progress.progress();
         long size = Math.min(length - offset, uploadPartSize);
         UploadPartRequest part;
         part = writeOperations.newUploadPartRequest(
@@ -525,7 +552,7 @@ public class CommitOperations {
 
       commitData.bindCommitData(parts);
       statistics.commitUploaded(length);
-      progress.progress();
+      // clear the threw flag.
       threw = false;
       return commitData;
     } finally {
@@ -536,6 +563,11 @@ public class CommitOperations {
           LOG.error("Failed to abort upload {} to {}", uploadId, destKey, e);
         }
       }
+      if (threw) {
+        tracker.failed();
+      }
+      // close tracker and so report statistics of success/failure
+      tracker.close();
     }
   }
 

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/commit/MagicCommitIntegration.java

@@ -27,6 +27,7 @@ import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.s3a.S3AFileSystem;
 import org.apache.hadoop.fs.s3a.Statistic;
 import org.apache.hadoop.fs.s3a.commit.magic.MagicCommitTracker;
+import org.apache.hadoop.fs.s3a.impl.StoreContext;
 
 import static org.apache.hadoop.fs.s3a.commit.MagicCommitPaths.*;
 
@@ -50,6 +51,8 @@ public class MagicCommitIntegration {
   private final S3AFileSystem owner;
   private final boolean magicCommitEnabled;
 
+  private final StoreContext storeContext;
+
   /**
    * Instantiate.
    * @param owner owner class
@@ -59,6 +62,7 @@ public class MagicCommitIntegration {
       boolean magicCommitEnabled) {
     this.owner = owner;
     this.magicCommitEnabled = magicCommitEnabled;
+    this.storeContext = owner.createStoreContext();
   }
 
   /**
@@ -94,10 +98,10 @@ public class MagicCommitIntegration {
       if (isMagicCommitPath(elements)) {
         final String destKey = keyOfFinalDestination(elements, key);
         String pendingsetPath = key + CommitConstants.PENDING_SUFFIX;
-        owner.getInstrumentation()
-            .incrementCounter(Statistic.COMMITTER_MAGIC_FILES_CREATED, 1);
+        storeContext.incrementStatistic(
+            Statistic.COMMITTER_MAGIC_FILES_CREATED);
         tracker = new MagicCommitTracker(path,
-            owner.getBucket(),
+            storeContext.getBucket(),
             key,
             destKey,
             pendingsetPath,

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/commit/PutTracker.java

@@ -24,6 +24,7 @@ import java.util.List;
 import com.amazonaws.services.s3.model.PartETag;
 
 import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.fs.statistics.IOStatistics;
 
 /**
  * Multipart put tracker.
@@ -68,6 +69,7 @@ public class PutTracker {
    * @param uploadId Upload ID
    * @param parts list of parts
    * @param bytesWritten bytes written
+   * @param iostatistics nullable IO statistics
    * @return true if the commit is to be initiated immediately.
    * False implies the output stream does not need to worry about
    * what happens.
@@ -75,7 +77,8 @@ public class PutTracker {
    */
   public boolean aboutToComplete(String uploadId,
       List<PartETag> parts,
-      long bytesWritten)
+      long bytesWritten,
+      final IOStatistics iostatistics)
       throws IOException {
     return true;
   }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/commit/files/PendingSet.java

@@ -27,6 +27,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -36,6 +37,8 @@ import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.s3a.commit.ValidationFailure;
+import org.apache.hadoop.fs.statistics.IOStatisticsSnapshot;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
 import org.apache.hadoop.util.JsonSerialization;
 
 import static org.apache.hadoop.fs.s3a.commit.CommitUtils.validateCollectionClass;
@@ -45,11 +48,22 @@ import static org.apache.hadoop.fs.s3a.commit.ValidationFailure.verify;
  * Persistent format for multiple pending commits.
  * Contains 0 or more {@link SinglePendingCommit} entries; validation logic
  * checks those values on load.
+ * <p>
+ * The statistics published through the {@link IOStatisticsSource}
+ * interface are the static ones marshalled with the commit data;
+ * they may be empty.
+ * </p>
+ * <p>
+ * As single commits are added via {@link #add(SinglePendingCommit)},
+ * any statistics from those commits are merged into the aggregate
+ * statistics, <i>and those of the single commit cleared.</i>
+ * </p>
  */
 @SuppressWarnings("unused")
 @InterfaceAudience.Private
 @InterfaceStability.Unstable
-public class PendingSet extends PersistentCommitData {
+public class PendingSet extends PersistentCommitData
+    implements IOStatisticsSource {
   private static final Logger LOG = LoggerFactory.getLogger(PendingSet.class);
 
   /**
@@ -57,7 +71,7 @@ public class PendingSet extends PersistentCommitData {
    * If this is changed the value of {@link #serialVersionUID} will change,
    * to avoid deserialization problems.
    */
-  public static final int VERSION = 2;
+  public static final int VERSION = 3;
 
   /**
    * Serialization ID: {@value}.
@@ -81,6 +95,12 @@ public class PendingSet extends PersistentCommitData {
    */
   private final Map<String, String> extraData = new HashMap<>(0);
 
+  /**
+   * IOStatistics.
+   */
+  @JsonProperty("iostatistics")
+  private IOStatisticsSnapshot iostats = new IOStatisticsSnapshot();
+
   public PendingSet() {
     this(0);
   }
@@ -133,6 +153,12 @@ public class PendingSet extends PersistentCommitData {
    */
   public void add(SinglePendingCommit commit) {
     commits.add(commit);
+    // add any statistics.
+    IOStatisticsSnapshot st = commit.getIOStatistics();
+    if (st != null) {
+      iostats.aggregate(st);
+      st.clear();
+    }
   }
 
   /**
@@ -225,4 +251,12 @@ public class PendingSet extends PersistentCommitData {
     this.jobId = jobId;
   }
 
+  @Override
+  public IOStatisticsSnapshot getIOStatistics() {
+    return iostats;
+  }
+
+  public void setIOStatistics(final IOStatisticsSnapshot ioStatistics) {
+    this.iostats = ioStatistics;
+  }
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/commit/files/SinglePendingCommit.java

@@ -31,6 +31,8 @@ import java.util.List;
 import java.util.Map;
 
 import com.amazonaws.services.s3.model.PartETag;
+import com.fasterxml.jackson.annotation.JsonProperty;
+
 import org.apache.hadoop.thirdparty.com.google.common.base.Preconditions;
 
 import org.apache.commons.lang3.StringUtils;
@@ -39,6 +41,8 @@ import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.s3a.commit.ValidationFailure;
+import org.apache.hadoop.fs.statistics.IOStatisticsSnapshot;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
 import org.apache.hadoop.util.JsonSerialization;
 
 import static org.apache.hadoop.fs.s3a.commit.CommitUtils.validateCollectionClass;
@@ -46,20 +50,25 @@ import static org.apache.hadoop.fs.s3a.commit.ValidationFailure.verify;
 import static org.apache.hadoop.util.StringUtils.join;
 
 /**
- * This is the serialization format for uploads yet to be committerd.
- *
+ * This is the serialization format for uploads yet to be committed.
+ * <p>
  * It's marked as {@link Serializable} so that it can be passed in RPC
  * calls; for this to work it relies on the fact that java.io ArrayList
  * and LinkedList are serializable. If any other list type is used for etags,
  * it must also be serialized. Jackson expects lists, and it is used
  * to persist to disk.
- *
+ * </p>
+ * <p>
+ * The statistics published through the {@link IOStatisticsSource}
+ * interface are the static ones marshalled with the commit data;
+ * they may be empty.
+ * </p>
  */
 @SuppressWarnings("unused")
 @InterfaceAudience.Private
 @InterfaceStability.Unstable
 public class SinglePendingCommit extends PersistentCommitData
-    implements Iterable<String> {
+    implements Iterable<String>, IOStatisticsSource {
 
   /**
    * Serialization ID: {@value}.
@@ -113,6 +122,12 @@ public class SinglePendingCommit extends PersistentCommitData
    */
   private Map<String, String> extraData = new HashMap<>(0);
 
+  /**
+   * IOStatistics.
+   */
+  @JsonProperty("iostatistics")
+  private IOStatisticsSnapshot iostats = new IOStatisticsSnapshot();
+
   /** Destination file size. */
   private long length;
 
@@ -439,4 +454,12 @@ public class SinglePendingCommit extends PersistentCommitData
     this.length = length;
   }
 
+  @Override
+  public IOStatisticsSnapshot getIOStatistics() {
+    return iostats;
+  }
+
+  public void setIOStatistics(final IOStatisticsSnapshot ioStatistics) {
+    this.iostats = ioStatistics;
+  }
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/commit/files/SuccessData.java

@@ -25,6 +25,7 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -34,6 +35,8 @@ import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.s3a.commit.ValidationFailure;
+import org.apache.hadoop.fs.statistics.IOStatisticsSnapshot;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
 import org.apache.hadoop.util.JsonSerialization;
 
 /**
@@ -62,9 +65,18 @@ import org.apache.hadoop.util.JsonSerialization;
 @SuppressWarnings("unused")
 @InterfaceAudience.Private
 @InterfaceStability.Unstable
-public class SuccessData extends PersistentCommitData {
+public class SuccessData extends PersistentCommitData
+    implements IOStatisticsSource {
+
   private static final Logger LOG = LoggerFactory.getLogger(SuccessData.class);
 
+  /**
+   * Supported version value: {@value}.
+   * If this is changed the value of {@link #serialVersionUID} will change,
+   * to avoid deserialization problems.
+   */
+  public static final int VERSION = 1;
+
   /**
    * Serialization ID: {@value}.
    */
@@ -75,7 +87,7 @@ public class SuccessData extends PersistentCommitData {
    * any other manifests: {@value}.
    */
   public static final String NAME
-      = "org.apache.hadoop.fs.s3a.commit.files.SuccessData/1";
+      = "org.apache.hadoop.fs.s3a.commit.files.SuccessData/" + VERSION;
 
   /**
    * Name of file; includes version marker.
@@ -126,6 +138,12 @@ public class SuccessData extends PersistentCommitData {
    */
   private List<String> filenames = new ArrayList<>(0);
 
+  /**
+   * IOStatistics.
+   */
+  @JsonProperty("iostatistics")
+  private IOStatisticsSnapshot iostats = new IOStatisticsSnapshot();
+
   @Override
   public void validate() throws ValidationFailure {
     ValidationFailure.verify(name != null,
@@ -350,4 +368,13 @@ public class SuccessData extends PersistentCommitData {
   public void setJobIdSource(final String jobIdSource) {
     this.jobIdSource = jobIdSource;
   }
+
+  @Override
+  public IOStatisticsSnapshot getIOStatistics() {
+    return iostats;
+  }
+
+  public void setIOStatistics(final IOStatisticsSnapshot ioStatistics) {
+    this.iostats = ioStatistics;
+  }
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/commit/magic/MagicCommitTracker.java

@@ -34,6 +34,8 @@ import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.s3a.WriteOperationHelper;
 import org.apache.hadoop.fs.s3a.commit.PutTracker;
 import org.apache.hadoop.fs.s3a.commit.files.SinglePendingCommit;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.fs.statistics.IOStatisticsSnapshot;
 
 /**
  * Put tracker for Magic commits.
@@ -102,6 +104,7 @@ public class MagicCommitTracker extends PutTracker {
    * @param uploadId Upload ID
    * @param parts list of parts
    * @param bytesWritten bytes written
+   * @param iostatistics nullable IO statistics
    * @return false, indicating that the commit must fail.
    * @throws IOException any IO problem.
    * @throws IllegalArgumentException bad argument
@@ -109,7 +112,8 @@ public class MagicCommitTracker extends PutTracker {
   @Override
   public boolean aboutToComplete(String uploadId,
       List<PartETag> parts,
-      long bytesWritten)
+      long bytesWritten,
+      final IOStatistics iostatistics)
       throws IOException {
     Preconditions.checkArgument(StringUtils.isNotEmpty(uploadId),
         "empty/null upload ID: "+ uploadId);
@@ -117,6 +121,15 @@ public class MagicCommitTracker extends PutTracker {
         "No uploaded parts list");
     Preconditions.checkArgument(!parts.isEmpty(),
         "No uploaded parts to save");
+
+    // put a 0-byte file with the name of the original under-magic path
+    PutObjectRequest originalDestPut = writer.createPutObjectRequest(
+        originalDestKey,
+        new ByteArrayInputStream(EMPTY),
+        0);
+    writer.uploadObject(originalDestPut);
+
+    // build the commit summary
     SinglePendingCommit commitData = new SinglePendingCommit();
     commitData.touch(System.currentTimeMillis());
     commitData.setDestinationKey(getDestKey());
@@ -126,6 +139,8 @@ public class MagicCommitTracker extends PutTracker {
     commitData.setText("");
     commitData.setLength(bytesWritten);
     commitData.bindCommitData(parts);
+    commitData.setIOStatistics(
+        new IOStatisticsSnapshot(iostatistics));
     byte[] bytes = commitData.toBytes();
     LOG.info("Uncommitted data pending to file {};"
             + " commit metadata for {} parts in {}. sixe: {} byte(s)",
@@ -138,12 +153,6 @@ public class MagicCommitTracker extends PutTracker {
         bytes.length);
     writer.uploadObject(put);
 
-    // now put a 0-byte file with the name of the original under-magic path
-    PutObjectRequest originalDestPut = writer.createPutObjectRequest(
-        originalDestKey,
-        new ByteArrayInputStream(EMPTY),
-        0);
-    writer.uploadObject(originalDestPut);
     return false;
   }
 

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/commit/magic/MagicS3GuardCommitter.java

@@ -37,6 +37,7 @@ import org.apache.hadoop.fs.s3a.commit.CommitConstants;
 import org.apache.hadoop.fs.s3a.commit.CommitUtilsWithMR;
 import org.apache.hadoop.fs.s3a.commit.files.PendingSet;
 import org.apache.hadoop.fs.s3a.commit.files.SinglePendingCommit;
+import org.apache.hadoop.fs.statistics.IOStatisticsLogging;
 import org.apache.hadoop.mapreduce.JobContext;
 import org.apache.hadoop.mapreduce.TaskAttemptContext;
 import org.apache.hadoop.mapreduce.TaskAttemptID;
@@ -47,6 +48,7 @@ import static org.apache.hadoop.fs.s3a.commit.CommitConstants.TASK_ATTEMPT_ID;
 import static org.apache.hadoop.fs.s3a.commit.CommitUtils.*;
 import static org.apache.hadoop.fs.s3a.commit.MagicCommitPaths.*;
 import static org.apache.hadoop.fs.s3a.commit.CommitUtilsWithMR.*;
+import static org.apache.hadoop.fs.statistics.IOStatisticsLogging.demandStringifyIOStatistics;
 
 /**
  * This is a dedicated committer which requires the "magic" directory feature
@@ -169,6 +171,8 @@ public class MagicS3GuardCommitter extends AbstractS3ACommitter {
       destroyThreadPool();
     }
     getCommitOperations().taskCompleted(true);
+    LOG.debug("aggregate statistics\n{}",
+        demandStringifyIOStatistics(getIOStatistics()));
   }
 
   /**
@@ -213,6 +217,8 @@ public class MagicS3GuardCommitter extends AbstractS3ACommitter {
         taskAttemptID.getTaskID().toString() +
         CommitConstants.PENDINGSET_SUFFIX);
     LOG.info("Saving work of {} to {}", taskAttemptID, taskOutcomePath);
+    LOG.debug("task statistics\n{}",
+        IOStatisticsLogging.demandStringifyIOStatisticsSource(pendingSet));
     try {
       // We will overwrite if there exists a pendingSet file already
       pendingSet.save(getDestFS(), taskOutcomePath, true);

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/ActiveOperationContext.java

@@ -0,0 +1,92 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.impl;
+
+import javax.annotation.Nullable;
+
+import java.util.Objects;
+import java.util.concurrent.atomic.AtomicLong;
+
+import org.apache.hadoop.fs.s3a.s3guard.BulkOperationState;
+import org.apache.hadoop.fs.s3a.statistics.S3AStatisticsContext;
+
+/**
+ * Context for any active operation.
+ */
+public class ActiveOperationContext {
+
+  /**
+   * An operation ID; currently just for logging...proper tracing needs more.
+   */
+  private final long operationId;
+
+  /**
+   * Statistics context.
+   */
+  private final S3AStatisticsContext statisticsContext;
+
+  /**
+   * S3Guard bulk operation state, if (currently) set.
+   */
+  @Nullable private BulkOperationState bulkOperationState;
+
+  public ActiveOperationContext(
+      final long operationId,
+      final S3AStatisticsContext statisticsContext,
+      @Nullable final BulkOperationState bulkOperationState) {
+    this.operationId = operationId;
+    this.statisticsContext = Objects.requireNonNull(statisticsContext,
+        "null statistics context");
+    this.bulkOperationState = bulkOperationState;
+  }
+
+  @Override
+  public String toString() {
+    final StringBuilder sb = new StringBuilder(
+        "ActiveOperation{");
+    sb.append("operationId=").append(operationId);
+    sb.append(", bulkOperationState=").append(bulkOperationState);
+    sb.append('}');
+    return sb.toString();
+  }
+
+  @Nullable
+  public BulkOperationState getBulkOperationState() {
+    return bulkOperationState;
+  }
+
+  public long getOperationId() {
+    return operationId;
+  }
+
+  public S3AStatisticsContext getS3AStatisticsContext() {
+    return statisticsContext;
+  }
+
+  private static final AtomicLong NEXT_OPERATION_ID = new AtomicLong(0);
+
+  /**
+   * Create an operation ID. The nature of it should be opaque.
+   * @return an ID for the constructor.
+   */
+  protected static long newOperationId() {
+    return NEXT_OPERATION_ID.incrementAndGet();
+  }
+
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/BulkDeleteRetryHandler.java

@@ -26,9 +26,9 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import org.apache.hadoop.fs.s3a.AWSClientIOException;
-import org.apache.hadoop.fs.s3a.S3AInstrumentation;
 import org.apache.hadoop.fs.s3a.S3AStorageStatistics;
 import org.apache.hadoop.fs.s3a.Statistic;
+import org.apache.hadoop.fs.s3a.statistics.S3AStatisticsContext;
 
 import static org.apache.hadoop.fs.s3a.S3AUtils.isThrottleException;
 import static org.apache.hadoop.fs.s3a.Statistic.IGNORED_ERRORS;
@@ -53,7 +53,7 @@ public class BulkDeleteRetryHandler extends AbstractStoreOperation {
    */
   public static final String XML_PARSE_BROKEN = "Failed to parse XML document";
 
-  private final S3AInstrumentation instrumentation;
+  private final S3AStatisticsContext instrumentation;
 
   private final S3AStorageStatistics storageStatistics;
 
@@ -84,7 +84,6 @@ public class BulkDeleteRetryHandler extends AbstractStoreOperation {
    */
   protected void incrementStatistic(Statistic statistic, long count) {
     instrumentation.incrementCounter(statistic, count);
-    storageStatistics.incrementCounter(statistic, count);
   }
 
   /**

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/CallableSupplier.java

@@ -20,6 +20,7 @@ package org.apache.hadoop.fs.s3a.impl;
 
 import javax.annotation.Nullable;
 import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.util.List;
 import java.util.concurrent.Callable;
 import java.util.concurrent.CancellationException;
@@ -31,7 +32,6 @@ import java.util.function.Supplier;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import org.apache.hadoop.fs.impl.WrappedIOException;
 import org.apache.hadoop.util.DurationInfo;
 
 import static org.apache.hadoop.fs.impl.FutureIOSupport.raiseInnerCause;
@@ -63,9 +63,9 @@ public final class CallableSupplier<T> implements Supplier {
     } catch (RuntimeException e) {
       throw e;
     } catch (IOException e) {
-      throw new WrappedIOException(e);
+      throw new UncheckedIOException(e);
     } catch (Exception e) {
-      throw new WrappedIOException(new IOException(e));
+      throw new UncheckedIOException(new IOException(e));
     }
   }
 
@@ -73,7 +73,7 @@ public final class CallableSupplier<T> implements Supplier {
    * Submit a callable into a completable future.
    * RTEs are rethrown.
    * Non RTEs are caught and wrapped; IOExceptions to
-   * {@link WrappedIOException} instances.
+   * {@code RuntimeIOException} instances.
    * @param executor executor.
    * @param call call to invoke
    * @param <T> type

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/ChangeTracker.java

@@ -18,8 +18,6 @@
 
 package org.apache.hadoop.fs.s3a.impl;
 
-import java.util.concurrent.atomic.AtomicLong;
-
 import com.amazonaws.AmazonServiceException;
 import com.amazonaws.SdkBaseException;
 import com.amazonaws.services.s3.model.CopyObjectRequest;
@@ -39,6 +37,7 @@ import org.apache.hadoop.fs.PathIOException;
 import org.apache.hadoop.fs.s3a.NoVersionAttributeException;
 import org.apache.hadoop.fs.s3a.RemoteFileChangedException;
 import org.apache.hadoop.fs.s3a.S3ObjectAttributes;
+import org.apache.hadoop.fs.s3a.statistics.ChangeTrackerStatistics;
 
 import static org.apache.hadoop.thirdparty.com.google.common.base.Preconditions.checkNotNull;
 
@@ -72,7 +71,7 @@ public class ChangeTracker {
    * Mismatch counter; expected to be wired up to StreamStatistics except
    * during testing.
    */
-  private final AtomicLong versionMismatches;
+  private final ChangeTrackerStatistics versionMismatches;
 
   /**
    * Revision identifier (e.g. eTag or versionId, depending on change
@@ -90,7 +89,7 @@ public class ChangeTracker {
    */
   public ChangeTracker(final String uri,
       final ChangeDetectionPolicy policy,
-      final AtomicLong versionMismatches,
+      final ChangeTrackerStatistics versionMismatches,
       final S3ObjectAttributes s3ObjectAttributes) {
     this.policy = checkNotNull(policy);
     this.uri = uri;
@@ -111,8 +110,8 @@ public class ChangeTracker {
   }
 
   @VisibleForTesting
-  public AtomicLong getVersionMismatches() {
-    return versionMismatches;
+  public long getVersionMismatches() {
+    return versionMismatches.getVersionMismatches();
   }
 
   /**
@@ -177,7 +176,7 @@ public class ChangeTracker {
       if (revisionId != null) {
         // the requirements of the change detection policy wasn't met: the
         // object was not returned.
-        versionMismatches.incrementAndGet();
+        versionMismatches.versionMismatchError();
         throw new RemoteFileChangedException(uri, operation,
             String.format(CHANGE_REPORTED_BY_S3
                     + " during %s"
@@ -235,7 +234,7 @@ public class ChangeTracker {
       // This isn't really going to be hit due to
       // https://github.com/aws/aws-sdk-java/issues/1644
       if (serviceException.getStatusCode() == SC_PRECONDITION_FAILED) {
-        versionMismatches.incrementAndGet();
+        versionMismatches.versionMismatchError();
         throw new RemoteFileChangedException(uri, operation, String.format(
             RemoteFileChangedException.PRECONDITIONS_FAILED
                 + " on %s."
@@ -292,10 +291,10 @@ public class ChangeTracker {
               uri,
               pos,
               operation,
-              versionMismatches.get());
+              versionMismatches.getVersionMismatches());
       if (pair.left) {
         // an mismatch has occurred: note it.
-        versionMismatches.incrementAndGet();
+        versionMismatches.versionMismatchError();
       }
       if (pair.right != null) {
         // there's an exception to raise: do it

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/ErrorTranslation.java

@@ -54,6 +54,18 @@ public class ErrorTranslation {
         && AwsErrorCodes.E_NO_SUCH_BUCKET.equals(e.getErrorCode());
   }
 
+  /**
+   * Does this exception indicate that a reference to an object
+   * returned a 404. Unknown bucket errors do not match this
+   * predicate.
+   * @param e exception.
+   * @return true if the status code and error code mean that the
+   * HEAD request returned 404 but the bucket was there.
+   */
+  public static boolean isObjectNotFound(AmazonServiceException e) {
+    return e.getStatusCode() == SC_404 && !isUnknownBucket(e);
+  }
+
   /**
    * AWS error codes explicitly recognized and processes specially;
    * kept in their own class for isolation.

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/InternalConstants.java

@@ -110,4 +110,11 @@ public final class InternalConstants {
    * Value: {@value}.
    */
   public static final int DEFAULT_UPLOAD_PART_COUNT_LIMIT = 10000;
+
+  /**
+   * Flag to enable AWS Statistics binding. As this is triggering
+   * problems related to region/endpoint setup, it is currently
+   * disabled.
+   */
+  public static final boolean AWS_SDK_METRICS_ENABLED = false;
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/ListingOperationCallbacks.java

@@ -29,6 +29,7 @@ import org.apache.hadoop.fs.s3a.S3ALocatedFileStatus;
 import org.apache.hadoop.fs.s3a.S3ListRequest;
 import org.apache.hadoop.fs.s3a.S3ListResult;
 import org.apache.hadoop.fs.s3a.s3guard.ITtlTimeProvider;
+import org.apache.hadoop.fs.statistics.DurationTrackerFactory;
 
 /**
  * These are all the callbacks which
@@ -44,12 +45,14 @@ public interface ListingOperationCallbacks {
    *
    * Retry policy: retry untranslated.
    * @param request request to initiate
+   * @param trackerFactory tracker with statistics to update
    * @return the results
    * @throws IOException if the retry invocation raises one (it shouldn't).
    */
   @Retries.RetryRaw
   CompletableFuture<S3ListResult> listObjectsAsync(
-          S3ListRequest request)
+          S3ListRequest request,
+          DurationTrackerFactory trackerFactory)
           throws IOException;
 
   /**
@@ -57,13 +60,15 @@ public interface ListingOperationCallbacks {
    * Retry policy: retry untranslated.
    * @param request last list objects request to continue
    * @param prevResult last paged result to continue from
+   * @param trackerFactory tracker with statistics to update
    * @return the next result object
    * @throws IOException none, just there for retryUntranslated.
    */
   @Retries.RetryRaw
   CompletableFuture<S3ListResult> continueListObjectsAsync(
           S3ListRequest request,
-          S3ListResult prevResult)
+          S3ListResult prevResult,
+          DurationTrackerFactory trackerFactory)
           throws IOException;
 
   /**
@@ -117,4 +122,5 @@ public interface ListingOperationCallbacks {
    * @return true iff the path is authoritative on the client.
    */
   boolean allowAuthoritative(Path p);
+
 }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/NetworkBinding.java

@@ -51,22 +51,18 @@ public class NetworkBinding {
           ".thirdparty.apache.http.conn.ssl.SSLConnectionSocketFactory";
 
   /**
-   * Configures the {@link com.amazonaws.thirdparty.apache.http.conn.ssl
-   * .SSLConnectionSocketFactory} used by the AWS SDK. A custom
-   * SSLConnectionSocketFactory can be set using the method
-   * {@link com.amazonaws.ApacheHttpClientConfig#setSslSocketFactory(
-   * com.amazonaws.thirdparty.apache.http.conn.socket.ConnectionSocketFactory)}.
-   * If {@link com.amazonaws.thirdparty.apache.http.conn.ssl
-   * .SSLConnectionSocketFactory} cannot be found on the classpath, the value
+   * Configures the {@code SSLConnectionSocketFactory} used by the AWS SDK.
+   * A custom Socket Factory can be set using the method
+   * {@code setSslSocketFactory()}.
+   * If {@code SSLConnectionSocketFactory} cannot be found on the classpath, the value
    * of {@link org.apache.hadoop.fs.s3a.Constants#SSL_CHANNEL_MODE} is ignored.
    *
    * @param conf the {@link Configuration} used to get the client specified
-   *             value of {@link org.apache.hadoop.fs.s3a.Constants
-   *             #SSL_CHANNEL_MODE}
-   * @param awsConf the {@link ClientConfiguration} to set the
+   *             value of {@code SSL_CHANNEL_MODE}
+   * @param awsConf the {@code ClientConfiguration} to set the
    *                SSLConnectionSocketFactory for.
    * @throws IOException if there is an error while initializing the
-   * {@link SSLSocketFactory} other than classloader problems.
+   * {@code SSLSocketFactory} other than classloader problems.
    */
   public static void bindSSLChannelMode(Configuration conf,
       ClientConfiguration awsConf) throws IOException {

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/S3AMultipartUploader.java

@@ -30,6 +30,7 @@ import java.util.Comparator;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.Set;
 import java.util.concurrent.CompletableFuture;
 
@@ -53,8 +54,11 @@ import org.apache.hadoop.fs.PathIOException;
 import org.apache.hadoop.fs.UploadHandle;
 import org.apache.hadoop.fs.impl.AbstractMultipartUploader;
 import org.apache.hadoop.fs.s3a.WriteOperations;
-import org.apache.hadoop.fs.s3a.impl.statistics.S3AMultipartUploaderStatistics;
+import org.apache.hadoop.fs.s3a.statistics.S3AMultipartUploaderStatistics;
 import org.apache.hadoop.fs.s3a.s3guard.BulkOperationState;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+
+import static org.apache.hadoop.fs.statistics.IOStatisticsLogging.ioStatisticsToString;
 
 /**
  * MultipartUploader for S3AFileSystem. This uses the S3 multipart
@@ -102,7 +106,7 @@ class S3AMultipartUploader extends AbstractMultipartUploader {
     this.builder = builder;
     this.writeOperations = writeOperations;
     this.context = context;
-    this.statistics = statistics;
+    this.statistics = Objects.requireNonNull(statistics);
   }
 
   @Override
@@ -113,6 +117,22 @@ class S3AMultipartUploader extends AbstractMultipartUploader {
     super.close();
   }
 
+  @Override
+  public IOStatistics getIOStatistics() {
+    return statistics.getIOStatistics();
+  }
+
+  @Override
+  public String toString() {
+    final StringBuilder sb = new StringBuilder(
+        "S3AMultipartUploader{");
+    sb.append("base=").append(getBasePath());
+    sb.append("; statistics=").append(
+        ioStatisticsToString(statistics.getIOStatistics()));
+    sb.append('}');
+    return sb.toString();
+  }
+
   /**
    * Retrieve the operation state; create one on demand if needed
    * <i>and there has been no unsuccessful attempt to create one.</i>

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/S3AMultipartUploaderBuilder.java

@@ -25,7 +25,7 @@ import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.impl.MultipartUploaderBuilderImpl;
 import org.apache.hadoop.fs.s3a.S3AFileSystem;
 import org.apache.hadoop.fs.s3a.WriteOperations;
-import org.apache.hadoop.fs.s3a.impl.statistics.S3AMultipartUploaderStatistics;
+import org.apache.hadoop.fs.s3a.statistics.S3AMultipartUploaderStatistics;
 
 /**
  * Builder for S3A multipart uploaders.

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/StoreContext.java

@@ -35,9 +35,9 @@ import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.s3a.Invoker;
 import org.apache.hadoop.fs.s3a.S3AFileStatus;
 import org.apache.hadoop.fs.s3a.S3AInputPolicy;
-import org.apache.hadoop.fs.s3a.S3AInstrumentation;
 import org.apache.hadoop.fs.s3a.S3AStorageStatistics;
 import org.apache.hadoop.fs.s3a.Statistic;
+import org.apache.hadoop.fs.s3a.statistics.S3AStatisticsContext;
 import org.apache.hadoop.fs.s3a.s3guard.ITtlTimeProvider;
 import org.apache.hadoop.fs.s3a.s3guard.MetadataStore;
 import org.apache.hadoop.security.UserGroupInformation;
@@ -90,7 +90,8 @@ public class StoreContext {
   private final Invoker invoker;
 
   /** Instrumentation and statistics. */
-  private final S3AInstrumentation instrumentation;
+  private final S3AStatisticsContext instrumentation;
+
   private final S3AStorageStatistics storageStatistics;
 
   /** Seek policy. */
@@ -131,7 +132,7 @@ public class StoreContext {
       final ExecutorService executor,
       final int executorCapacity,
       final Invoker invoker,
-      final S3AInstrumentation instrumentation,
+      final S3AStatisticsContext instrumentation,
       final S3AStorageStatistics storageStatistics,
       final S3AInputPolicy inputPolicy,
       final ChangeDetectionPolicy changeDetectionPolicy,
@@ -188,7 +189,12 @@ public class StoreContext {
     return invoker;
   }
 
-  public S3AInstrumentation getInstrumentation() {
+  /**
+   * Get the statistics context for this StoreContext.
+   * @return the statistics context this store context was created
+   * with.
+   */
+  public S3AStatisticsContext getInstrumentation() {
     return instrumentation;
   }
 
@@ -270,7 +276,6 @@ public class StoreContext {
    */
   public void incrementStatistic(Statistic statistic, long count) {
     instrumentation.incrementCounter(statistic, count);
-    storageStatistics.incrementCounter(statistic, count);
   }
 
   /**

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/StoreContextBuilder.java

@@ -24,8 +24,8 @@ import java.util.concurrent.ExecutorService;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.s3a.Invoker;
 import org.apache.hadoop.fs.s3a.S3AInputPolicy;
-import org.apache.hadoop.fs.s3a.S3AInstrumentation;
 import org.apache.hadoop.fs.s3a.S3AStorageStatistics;
+import org.apache.hadoop.fs.s3a.statistics.S3AStatisticsContext;
 import org.apache.hadoop.fs.s3a.s3guard.ITtlTimeProvider;
 import org.apache.hadoop.fs.s3a.s3guard.MetadataStore;
 import org.apache.hadoop.security.UserGroupInformation;
@@ -51,7 +51,7 @@ public class StoreContextBuilder {
 
   private Invoker invoker;
 
-  private S3AInstrumentation instrumentation;
+  private S3AStatisticsContext instrumentation;
 
   private S3AStorageStatistics storageStatistics;
 
@@ -112,7 +112,7 @@ public class StoreContextBuilder {
   }
 
   public StoreContextBuilder setInstrumentation(
-      final S3AInstrumentation instr) {
+      final S3AStatisticsContext instr) {
     this.instrumentation = instr;
     return this;
   }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/s3guard/DynamoDBMetadataStore.java

@@ -21,6 +21,7 @@ package org.apache.hadoop.fs.s3a.s3guard;
 import javax.annotation.Nullable;
 import java.io.IOException;
 import java.io.InterruptedIOException;
+import java.io.UncheckedIOException;
 import java.net.URI;
 import java.nio.file.AccessDeniedException;
 import java.util.ArrayList;
@@ -80,8 +81,8 @@ import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.PathIOException;
 import org.apache.hadoop.fs.RemoteIterator;
-import org.apache.hadoop.fs.impl.FunctionsRaisingIOE;
-import org.apache.hadoop.fs.impl.WrappedIOException;
+import org.apache.hadoop.util.functional.CallableRaisingIOE;
+import org.apache.hadoop.util.functional.RemoteIterators;
 import org.apache.hadoop.fs.s3a.AWSCredentialProviderList;
 import org.apache.hadoop.fs.s3a.AWSServiceThrottledException;
 import org.apache.hadoop.fs.s3a.Constants;
@@ -451,7 +452,8 @@ public class DynamoDBMetadataStore implements MetadataStore,
     owner = fs;
     conf = owner.getConf();
     StoreContext context = owner.createStoreContext();
-    instrumentation = context.getInstrumentation().getS3GuardInstrumentation();
+    instrumentation = context.getInstrumentation()
+        .getS3GuardInstrumentation();
     username = context.getUsername();
     executor = MoreExecutors.listeningDecorator(
         context.createThrottledExecutor());
@@ -641,8 +643,9 @@ public class DynamoDBMetadataStore implements MetadataStore,
       LOG.debug("Subtree path {} is deleted; this will be a no-op", path);
       return;
     }
-    deleteEntries(new InternalIterators.PathFromRemoteStatusIterator(
-        new DescendantsIterator(this, meta)),
+    deleteEntries(RemoteIterators.mappingRemoteIterator(
+        new DescendantsIterator(this, meta),
+        FileStatus::getPath),
         operationState);
   }
 
@@ -651,8 +654,7 @@ public class DynamoDBMetadataStore implements MetadataStore,
   public void deletePaths(Collection<Path> paths,
       final BulkOperationState operationState)
       throws IOException {
-    deleteEntries(
-        new InternalIterators.RemoteIteratorFromIterator<>(paths.iterator()),
+    deleteEntries(RemoteIterators.remoteIteratorFromIterable(paths),
         operationState);
   }
 
@@ -829,7 +831,7 @@ public class DynamoDBMetadataStore implements MetadataStore,
       for (Item item : wrapWithRetries(items)) {
         metas.add(itemToPathMetadata(item, username));
       }
-    } catch (WrappedIOException e) {
+    } catch (UncheckedIOException e) {
       // failure in the iterators; unwrap.
       throw e.getCause();
     }
@@ -1637,7 +1639,7 @@ public class DynamoDBMetadataStore implements MetadataStore,
       Set<Path> clearedParentPathSet = new HashSet<>();
       // declare the operation to delete a batch as a function so
       // as to keep the code consistent across multiple uses.
-      FunctionsRaisingIOE.CallableRaisingIOE<Void> deleteBatchOperation =
+      CallableRaisingIOE<Void> deleteBatchOperation =
           () -> {
             // lowest path entries get deleted first.
             deletionBatch.sort(PathOrderComparators.TOPMOST_PATH_LAST);

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/s3guard/InternalIterators.java

@@ -1,91 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.apache.hadoop.fs.s3a.s3guard;
-
-import java.io.IOException;
-import java.util.Iterator;
-
-import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.fs.RemoteIterator;
-import org.apache.hadoop.fs.s3a.S3AFileStatus;
-
-/**
- * Internal iterators.
- */
-final class InternalIterators {
-
-  private InternalIterators() {
-  }
-
-  /**
-   * From a remote status iterator, build a path iterator.
-   */
-  static final class PathFromRemoteStatusIterator implements
-      RemoteIterator<Path> {
-
-    private final RemoteIterator<S3AFileStatus> source;
-
-    /**
-     * Construct.
-     * @param source source iterator.
-     */
-    PathFromRemoteStatusIterator(final RemoteIterator<S3AFileStatus> source) {
-      this.source = source;
-    }
-
-    @Override
-    public boolean hasNext() throws IOException {
-      return source.hasNext();
-    }
-
-    @Override
-    public Path next() throws IOException {
-      return source.next().getPath();
-    }
-  }
-
-  /**
-   * From a classic java.util.Iterator, build a Hadoop remote iterator.
-   * @param <T> type of iterated value.
-   */
-  static final class RemoteIteratorFromIterator<T> implements
-      RemoteIterator<T> {
-
-    private final Iterator<T> source;
-
-    /**
-     * Construct.
-     * @param source source iterator.
-     */
-    RemoteIteratorFromIterator(final Iterator<T> source) {
-      this.source = source;
-    }
-
-    @Override
-    public boolean hasNext() {
-      return source.hasNext();
-    }
-
-    @Override
-    public T next() {
-      return source.next();
-    }
-  }
-
-}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/s3guard/RetryingCollection.java

@@ -19,9 +19,9 @@
 package org.apache.hadoop.fs.s3a.s3guard;
 
 import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.util.Iterator;
 
-import org.apache.hadoop.fs.impl.WrappedIOException;
 import org.apache.hadoop.fs.s3a.Invoker;
 import org.apache.hadoop.fs.s3a.Retries;
 
@@ -88,7 +88,7 @@ class RetryingCollection<T> implements Iterable<T> {
 
     /**
      * {@inheritDoc}.
-     * @throws WrappedIOException for IO failure, including throttling.
+     * @throws UncheckedIOException for IO failure, including throttling.
      */
     @Override
     @Retries.RetryTranslated
@@ -100,13 +100,13 @@ class RetryingCollection<T> implements Iterable<T> {
             true,
             iterator::hasNext);
       } catch (IOException e) {
-        throw new WrappedIOException(e);
+        throw new UncheckedIOException(e);
       }
     }
 
     /**
      * {@inheritDoc}.
-     * @throws WrappedIOException for IO failure, including throttling.
+     * @throws UncheckedIOException for IO failure, including throttling.
      */
     @Override
     @Retries.RetryTranslated
@@ -118,7 +118,7 @@ class RetryingCollection<T> implements Iterable<T> {
             true,
             iterator::next);
       } catch (IOException e) {
-        throw new WrappedIOException(e);
+        throw new UncheckedIOException(e);
       }
     }
   }

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/select/SelectInputStream.java

@@ -39,9 +39,9 @@ import org.apache.hadoop.fs.FSExceptionMessages;
 import org.apache.hadoop.fs.FSInputStream;
 import org.apache.hadoop.fs.PathIOException;
 import org.apache.hadoop.fs.s3a.Retries;
-import org.apache.hadoop.fs.s3a.S3AInstrumentation;
 import org.apache.hadoop.fs.s3a.S3AReadOpContext;
 import org.apache.hadoop.fs.s3a.S3ObjectAttributes;
+import org.apache.hadoop.fs.s3a.statistics.S3AInputStreamStatistics;
 import org.apache.hadoop.io.IOUtils;
 
 import static org.apache.hadoop.thirdparty.com.google.common.base.Preconditions.checkNotNull;
@@ -103,7 +103,7 @@ public class SelectInputStream extends FSInputStream implements
 
   private final S3AReadOpContext readContext;
 
-  private final S3AInstrumentation.InputStreamStatistics streamStatistics;
+  private final S3AInputStreamStatistics streamStatistics;
 
   private long readahead;
 
@@ -130,7 +130,7 @@ public class SelectInputStream extends FSInputStream implements
     this.uri = "s3a://" + this.bucket + "/" + this.key;
     this.readContext = readContext;
     this.readahead = readContext.getReadahead();
-    this.streamStatistics = readContext.getInstrumentation()
+    this.streamStatistics = readContext.getS3AStatisticsContext()
         .newInputStreamStatistics();
     SelectRecordsInputStream stream = once(
         "S3 Select",
@@ -204,7 +204,7 @@ public class SelectInputStream extends FSInputStream implements
     long skipped = once("skip", uri, () -> wrappedStream.skip(n));
     pos.addAndGet(skipped);
     // treat as a forward skip for stats
-    streamStatistics.seekForwards(skipped);
+    streamStatistics.seekForwards(skipped, skipped);
     return skipped;
   }
 
@@ -331,7 +331,7 @@ public class SelectInputStream extends FSInputStream implements
         bytesSkipped++;
       }
       // read has finished.
-      streamStatistics.seekForwards(bytesSkipped);
+      streamStatistics.seekForwards(bytesSkipped, bytesSkipped);
     }
   }
 
@@ -428,7 +428,7 @@ public class SelectInputStream extends FSInputStream implements
    */
   @InterfaceAudience.Private
   @InterfaceStability.Unstable
-  public S3AInstrumentation.InputStreamStatistics getS3AStreamStatistics() {
+  public S3AInputStreamStatistics getS3AStreamStatistics() {
     return streamStatistics;
   }
 

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/BlockOutputStreamStatistics.java

@@ -0,0 +1,137 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics;
+
+import java.io.Closeable;
+import java.time.Duration;
+
+/**
+ * Block output stream statistics.
+ */
+public interface BlockOutputStreamStatistics extends Closeable,
+    S3AStatisticInterface {
+
+  /**
+   * Block is queued for upload.
+   * @param blockSize block size.
+   */
+  void blockUploadQueued(int blockSize);
+
+  /**
+   * Queued block has been scheduled for upload.
+   * @param timeInQueue time in the queue.
+   * @param blockSize block size.
+   */
+  void blockUploadStarted(Duration timeInQueue, int blockSize);
+
+  /**
+   * A block upload has completed. Duration excludes time in the queue.
+   * @param timeSinceUploadStarted time in since the transfer began.
+   * @param blockSize block size
+   */
+  void blockUploadCompleted(Duration timeSinceUploadStarted, int blockSize);
+
+  /**
+   *  A block upload has failed. Duration excludes time in the queue.
+   * <p>
+   *  A final transfer completed event is still expected, so this
+   *  does not decrement the active block counter.
+   * </p>
+   * @param timeSinceUploadStarted time in since the transfer began.
+   * @param blockSize block size
+   */
+  void blockUploadFailed(Duration timeSinceUploadStarted, int blockSize);
+
+  /**
+   * Intermediate report of bytes uploaded.
+   * @param byteCount bytes uploaded
+   */
+  void bytesTransferred(long byteCount);
+
+  /**
+   * Note exception in a multipart complete.
+   * @param count count of exceptions
+   */
+  void exceptionInMultipartComplete(int count);
+
+  /**
+   * Note an exception in a multipart abort.
+   */
+  void exceptionInMultipartAbort();
+
+  /**
+   * Get the number of bytes pending upload.
+   * @return the number of bytes in the pending upload state.
+   */
+  long getBytesPendingUpload();
+
+  /**
+   * Data has been uploaded to be committed in a subsequent operation;
+   * to be called at the end of the write.
+   * @param size size in bytes
+   */
+  void commitUploaded(long size);
+
+  int getBlocksAllocated();
+
+  int getBlocksReleased();
+
+  /**
+   * Get counters of blocks actively allocated; may be inaccurate
+   * if the numbers change during the (non-synchronized) calculation.
+   * @return the number of actively allocated blocks.
+   */
+  int getBlocksActivelyAllocated();
+
+  /**
+   * Record bytes written.
+   * @param count number of bytes
+   */
+  void writeBytes(long count);
+
+  /**
+   * Get the current count of bytes written.
+   * @return the counter value.
+   */
+  long getBytesWritten();
+
+  /**
+   * A block has been allocated.
+   */
+  void blockAllocated();
+
+  /**
+   * A block has been released.
+   */
+  void blockReleased();
+
+  /**
+   * Get the value of a counter.
+   * @param name counter name
+   * @return the value or null if no matching counter was found.
+   */
+  Long lookupCounterValue(String name);
+
+  /**
+   * Get the value of a gauge.
+   * @param name gauge name
+   * @return the value or null if no matching gauge was found.
+   */
+  Long lookupGaugeValue(String name);
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/ChangeTrackerStatistics.java

@@ -0,0 +1,36 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics;
+
+/**
+ * Interface for change tracking statistics.
+ */
+public interface ChangeTrackerStatistics {
+
+  /**
+   * A version mismatch was detected.
+   */
+  void versionMismatchError();
+
+  /**
+   * How many version mismatches have occurred.
+   * @return counter of mismatches.
+   */
+  long getVersionMismatches();
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/CommitterStatistics.java

@@ -0,0 +1,66 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics;
+
+/**
+ * Statistics for S3A committers.
+ */
+public interface CommitterStatistics
+    extends S3AStatisticInterface {
+
+  /** A commit has been created. */
+  void commitCreated();
+
+  /**
+   * Data has been uploaded to be committed in a subsequent operation.
+   * @param size size in bytes
+   */
+  void commitUploaded(long size);
+
+  /**
+   * A commit has been completed.
+   * @param size size in bytes
+   */
+  void commitCompleted(long size);
+
+  /** A commit has been aborted. */
+  void commitAborted();
+
+  /**
+   * A commit was reverted.
+   */
+  void commitReverted();
+
+  /**
+   * A commit failed.
+   */
+  void commitFailed();
+
+  /**
+   * Note that a task has completed.
+   * @param success success flag
+   */
+  void taskCompleted(boolean success);
+
+  /**
+   * Note that a job has completed.
+   * @param success success flag
+   */
+  void jobCompleted(boolean success);
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/CountersAndGauges.java

@@ -0,0 +1,72 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics;
+
+import java.time.Duration;
+
+import org.apache.hadoop.fs.s3a.Statistic;
+
+/**
+ * This is the foundational API for collecting S3A statistics.
+ */
+public interface CountersAndGauges {
+
+  /**
+   * Increment a specific counter.
+   * No-op if not defined.
+   * @param op operation
+   * @param count increment value
+   */
+  void incrementCounter(Statistic op, long count);
+
+  /**
+   * Increment a specific gauge.
+   * No-op if not defined.
+   * @param op operation
+   * @param count increment value
+   * @throws ClassCastException if the metric is of the wrong type
+   */
+  void incrementGauge(Statistic op, long count);
+
+  /**
+   * Decrement a specific gauge.
+   * No-op if not defined.
+   * @param op operation
+   * @param count increment value
+   * @throws ClassCastException if the metric is of the wrong type
+   */
+  void decrementGauge(Statistic op, long count);
+
+  /**
+   * Add a value to a quantiles statistic. No-op if the quantile
+   * isn't found.
+   * @param op operation to look up.
+   * @param value value to add.
+   * @throws ClassCastException if the metric is not a Quantiles.
+   */
+  void addValueToQuantiles(Statistic op, long value);
+
+  /**
+   * Record a duration.
+   * @param op operation
+   * @param success was the operation a success?
+   * @param duration how long did it take
+   */
+  void recordDuration(Statistic op, boolean success, Duration duration);
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/DelegationTokenStatistics.java

@@ -0,0 +1,28 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics;
+
+/**
+ * Instrumentation exported to for S3A Delegation Token support.
+ */
+public interface DelegationTokenStatistics extends S3AStatisticInterface {
+
+  /** A token has been issued. */
+  void tokenIssued();
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/S3AInputStreamStatistics.java

@@ -0,0 +1,191 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics;
+
+import org.apache.hadoop.fs.statistics.DurationTracker;
+
+/**
+ * Statistics updated by a
+ * {@link org.apache.hadoop.fs.s3a.S3AInputStream} during its use.
+ * It also contains getters for tests.
+ */
+public interface S3AInputStreamStatistics extends AutoCloseable,
+    S3AStatisticInterface {
+
+  /**
+   * Seek backwards, incrementing the seek and backward seek counters.
+   * @param negativeOffset how far was the seek?
+   * This is expected to be negative.
+   */
+  void seekBackwards(long negativeOffset);
+
+  /**
+   * Record a forward seek, adding a seek operation, a forward
+   * seek operation, and any bytes skipped.
+   * @param skipped bytes moved forward in stream
+   * @param bytesReadInSeek number of bytes skipped by reading from the stream.
+   * If the seek was implemented by a close + reopen, set this to zero.
+   */
+  void seekForwards(long skipped, long bytesReadInSeek);
+
+  /**
+   * The inner stream was opened.
+   * The return value is used in the input stream to decide whether it is
+   * the initial vs later count.
+   * @return the previous count or zero if this is the first opening.
+   */
+  long streamOpened();
+
+  /**
+   * The inner stream was closed.
+   * @param abortedConnection flag to indicate the stream was aborted,
+   * rather than closed cleanly
+   * @param remainingInCurrentRequest the number of bytes remaining in
+   * the current request.
+   */
+  void streamClose(boolean abortedConnection,
+      long remainingInCurrentRequest);
+
+  /**
+   * An ignored stream read exception was received.
+   */
+  void readException();
+
+  /**
+   * Increment the bytes read counter by the number of bytes;
+   * no-op if the argument is negative.
+   * @param bytes number of bytes read
+   */
+  void bytesRead(long bytes);
+
+  /**
+   * A {@code read(byte[] buf, int off, int len)} operation has started.
+   * @param pos starting position of the read
+   * @param len length of bytes to read
+   */
+  void readOperationStarted(long pos, long len);
+
+  /**
+   * A {@code PositionedRead.read(position, buffer, offset, length)}
+   * operation has just started.
+   * @param pos starting position of the read
+   * @param len length of bytes to read
+   */
+  void readFullyOperationStarted(long pos, long len);
+
+  /**
+   * A read operation has completed.
+   * @param requested number of requested bytes
+   * @param actual the actual number of bytes
+   */
+  void readOperationCompleted(int requested, int actual);
+
+  @Override
+  void close();
+
+  /**
+   * The input policy has been switched.
+   * @param updatedPolicy enum value of new policy.
+   */
+  void inputPolicySet(int updatedPolicy);
+
+  /**
+   * Get a reference to the change tracker statistics for this
+   * stream.
+   * @return a reference to the change tracker statistics
+   */
+  ChangeTrackerStatistics getChangeTrackerStatistics();
+
+  /**
+   * A stream {@code unbuffer()} call has been made.
+   */
+  void unbuffered();
+
+  long getCloseOperations();
+
+  long getClosed();
+
+  long getAborted();
+
+  long getForwardSeekOperations();
+
+  long getBackwardSeekOperations();
+
+  /**
+   * The bytes read in read() operations.
+   * @return the number of bytes returned to the caller.
+   */
+  long getBytesRead();
+
+  /**
+   * The total number of bytes read, including
+   * all read and discarded when closing streams
+   * or skipped during seek calls.
+   * @return the total number of bytes read from
+   * S3.
+   */
+  long getTotalBytesRead();
+
+  long getBytesSkippedOnSeek();
+
+  long getBytesBackwardsOnSeek();
+
+  long getBytesReadInClose();
+
+  long getBytesDiscardedInAbort();
+
+  long getOpenOperations();
+
+  long getSeekOperations();
+
+  long getReadExceptions();
+
+  long getReadOperations();
+
+  long getReadFullyOperations();
+
+  long getReadsIncomplete();
+
+  long getPolicySetCount();
+
+  long getVersionMismatches();
+
+  long getInputPolicy();
+
+  /**
+   * Get the value of a counter.
+   * @param name counter name
+   * @return the value or null if no matching counter was found.
+   */
+  Long lookupCounterValue(String name);
+
+  /**
+   * Get the value of a gauge.
+   * @param name gauge name
+   * @return the value or null if no matching gauge was found.
+   */
+  Long lookupGaugeValue(String name);
+
+  /**
+   * Initiate a GET request.
+   * @return duration tracker;
+   */
+  DurationTracker initiateGetRequest();
+
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/statistics/S3AMultipartUploaderStatistics.java → hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/S3AMultipartUploaderStatistics.java

@@ -16,14 +16,17 @@
  * limitations under the License.
  */
 
-package org.apache.hadoop.fs.s3a.impl.statistics;
+package org.apache.hadoop.fs.s3a.statistics;
 
 import java.io.Closeable;
 
 /**
  * Statistics for the S3A multipart uploader.
+ * It is expected to act as the statistics source for
+ * the uploader.
  */
-public interface S3AMultipartUploaderStatistics extends Closeable {
+public interface S3AMultipartUploaderStatistics extends Closeable,
+    S3AStatisticInterface {
 
   void instantiated();
 

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/S3AStatisticInterface.java

@@ -0,0 +1,32 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics;
+
+import org.apache.hadoop.fs.statistics.DurationTrackerFactory;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
+
+/**
+ * Base Interface for S3A Statistics, as a way of managing
+ * them.
+ */
+public interface S3AStatisticInterface extends IOStatisticsSource,
+    DurationTrackerFactory {
+
+
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/S3AStatisticsContext.java

@@ -0,0 +1,69 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics;
+
+import org.apache.hadoop.fs.s3a.s3guard.MetastoreInstrumentation;
+
+/**
+ * This is the statistics context for ongoing operations in S3A.
+ */
+public interface S3AStatisticsContext extends CountersAndGauges {
+
+  /**
+   * Get the metastore instrumentation.
+   * @return an instance of the metastore statistics tracking.
+   */
+  MetastoreInstrumentation getS3GuardInstrumentation();
+
+  /**
+   * Create a stream input statistics instance.
+   * @return the new instance
+   */
+  S3AInputStreamStatistics newInputStreamStatistics();
+
+  /**
+   * Create a new instance of the committer statistics.
+   * @return a new committer statistics instance
+   */
+  CommitterStatistics newCommitterStatistics();
+
+  /**
+   * Create a stream output statistics instance.
+   * @return the new instance
+   */
+  BlockOutputStreamStatistics newOutputStreamStatistics();
+
+  /**
+   * Create a delegation token statistics instance.
+   * @return an instance of delegation token statistics
+   */
+  DelegationTokenStatistics newDelegationTokenStatistics();
+
+  /**
+   * Create a StatisticsFromAwsSdk instance.
+   * @return an instance of StatisticsFromAwsSdk
+   */
+  StatisticsFromAwsSdk newStatisticsFromAwsSdk();
+
+  /**
+   * Creaet a multipart statistics collector.
+   * @return an instance
+   */
+  S3AMultipartUploaderStatistics createMultipartUploaderStatistics();
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/StatisticTypeEnum.java

@@ -0,0 +1,46 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics;
+
+/**
+ * Enum of statistic types.
+ */
+public enum StatisticTypeEnum {
+
+  /**
+   * Counter.
+   */
+  TYPE_COUNTER,
+
+  /**
+   * Duration.
+   */
+  TYPE_DURATION,
+
+  /**
+   * Gauge.
+   */
+  TYPE_GAUGE,
+
+  /**
+   * Quantile.
+   */
+  TYPE_QUANTILE,
+
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/StatisticsFromAwsSdk.java

@@ -0,0 +1,81 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics;
+
+import java.time.Duration;
+
+import org.apache.hadoop.fs.s3a.statistics.impl.AwsStatisticsCollector;
+
+/**
+ * interface to receive statistics events from the AWS SDK
+ * by way of {@link AwsStatisticsCollector}.
+ */
+public interface StatisticsFromAwsSdk {
+
+  /**
+   * Record a number of AWS requests.
+   * @param count number of events.
+   */
+  void updateAwsRequestCount(long count);
+
+  /**
+   * Record a number of AWS request retries.
+   * @param count number of events.
+   */
+  void updateAwsRetryCount(long count);
+
+  /**
+   * Record a number of throttle exceptions received.
+   * @param count number of events.
+   */
+  void updateAwsThrottleExceptionsCount(long count);
+
+  /**
+   * Record how long a request took overall.
+   * @param duration duration of operation.
+   */
+  void noteAwsRequestTime(Duration duration);
+
+  /**
+   * Record how long a request took to execute on the
+   * client.
+   * @param duration duration of operation.
+   */
+  void noteAwsClientExecuteTime(Duration duration);
+
+  /**
+   * Record how long a request took to marshall into
+   * XML.
+   * @param duration duration of operation.
+   */
+  void noteRequestMarshallTime(Duration duration);
+
+  /**
+   * Record how long a request took to sign, including
+   * any calls to EC2 credential endpoints.
+   * @param duration duration of operation.
+   */
+  void noteRequestSigningTime(Duration duration);
+
+  /**
+   * Record how long it took to process the response.
+   * @param duration duration of operation.
+   */
+  void noteResponseProcessingTime(Duration duration);
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/impl/AbstractS3AStatisticsSource.java

@@ -0,0 +1,111 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics.impl;
+
+import org.apache.hadoop.fs.statistics.DurationTracker;
+import org.apache.hadoop.fs.statistics.DurationTrackerFactory;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
+import org.apache.hadoop.fs.statistics.impl.IOStatisticsStore;
+
+/**
+ * Base class for implementing IOStatistics sources in the S3 module.
+ * <p>
+ * A lot of the methods are very terse, because S3AInstrumentation has
+ * verbose methods of similar names; the short ones always
+ * refer to the inner class and not any superclass method.
+ * </p>
+ */
+public abstract class AbstractS3AStatisticsSource implements
+    IOStatisticsSource, DurationTrackerFactory {
+
+  private IOStatisticsStore ioStatistics;
+
+  protected AbstractS3AStatisticsSource() {
+  }
+
+  @Override
+  public IOStatisticsStore getIOStatistics() {
+    return ioStatistics;
+  }
+
+  /**
+   * Setter.
+   * this must be called in the subclass constructor with
+   * whatever
+   * @param statistics statistics to set
+   */
+  protected void setIOStatistics(final IOStatisticsStore statistics) {
+    this.ioStatistics = statistics;
+  }
+
+  /**
+   * Increment a named counter by 1.
+   * @param name counter name
+   * @return the updated value or, if the counter is unknown: 0
+   */
+  public long incCounter(String name) {
+    return incCounter(name, 1);
+  }
+
+  /**DefaultS3ClientFactoryDefaultS3ClientFactory
+   * Increment a named counter by 1.
+   * @param name counter name
+   * @param value value to increment by
+   * @return the updated value or, if the counter is unknown: 0
+   */
+  public long incCounter(String name, long value) {
+    return ioStatistics.incrementCounter(name, value);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public Long lookupCounterValue(final String name) {
+    return ioStatistics.counters().get(name);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public Long lookupGaugeValue(final String name) {
+    return ioStatistics.gauges().get(name);
+  }
+
+  public long incGauge(String name, long v) {
+    return ioStatistics.incrementGauge(name, v);
+  }
+
+  public long incGauge(String name) {
+    return incGauge(name, 1);
+  }
+
+  @Override
+  public String toString() {
+    final StringBuilder sb = new StringBuilder(
+        "AbstractS3AStatisticsSource{");
+    sb.append(ioStatistics);
+    sb.append('}');
+    return sb.toString();
+  }
+
+  @Override
+  public DurationTracker trackDuration(final String key, final long count) {
+    return getIOStatistics().trackDuration(key, count);
+  }
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/impl/AwsStatisticsCollector.java

@@ -0,0 +1,129 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics.impl;
+
+import java.time.Duration;
+import java.util.function.Consumer;
+import java.util.function.LongConsumer;
+
+import com.amazonaws.Request;
+import com.amazonaws.Response;
+import com.amazonaws.metrics.RequestMetricCollector;
+import com.amazonaws.util.TimingInfo;
+
+import org.apache.hadoop.fs.s3a.statistics.StatisticsFromAwsSdk;
+
+import static com.amazonaws.util.AWSRequestMetrics.Field.ClientExecuteTime;
+import static com.amazonaws.util.AWSRequestMetrics.Field.HttpClientRetryCount;
+import static com.amazonaws.util.AWSRequestMetrics.Field.HttpRequestTime;
+import static com.amazonaws.util.AWSRequestMetrics.Field.RequestCount;
+import static com.amazonaws.util.AWSRequestMetrics.Field.RequestMarshallTime;
+import static com.amazonaws.util.AWSRequestMetrics.Field.RequestSigningTime;
+import static com.amazonaws.util.AWSRequestMetrics.Field.ResponseProcessingTime;
+import static com.amazonaws.util.AWSRequestMetrics.Field.ThrottleException;
+
+/**
+ * Collect statistics from the AWS SDK and forward to an instance of
+ * {@link StatisticsFromAwsSdk} and thence into the S3A statistics.
+ * <p>
+ * See {@code com.facebook.presto.hive.s3.PrestoS3FileSystemMetricCollector}
+ * for the inspiration for this.
+ * <p>
+ * See {@code com.amazonaws.util.AWSRequestMetrics} for metric names.
+ */
+public class AwsStatisticsCollector extends RequestMetricCollector {
+
+  /**
+   * final destination of updates.
+   */
+  private final StatisticsFromAwsSdk collector;
+
+  /**
+   * Instantiate.
+   * @param collector final destination of updates
+   */
+  public AwsStatisticsCollector(final StatisticsFromAwsSdk collector) {
+    this.collector = collector;
+  }
+
+  /**
+   * This is the callback from the AWS SDK where metrics
+   * can be collected.
+   * @param request AWS request
+   * @param response AWS response
+   */
+  @Override
+  public void collectMetrics(
+      final Request<?> request,
+      final Response<?> response) {
+
+    TimingInfo timingInfo = request.getAWSRequestMetrics().getTimingInfo();
+
+    counter(timingInfo, HttpClientRetryCount.name(),
+        collector::updateAwsRetryCount);
+    counter(timingInfo, RequestCount.name(),
+        collector::updateAwsRequestCount);
+    counter(timingInfo, ThrottleException.name(),
+        collector::updateAwsThrottleExceptionsCount);
+
+    timing(timingInfo, ClientExecuteTime.name(),
+        collector::noteAwsClientExecuteTime);
+    timing(timingInfo, HttpRequestTime.name(),
+        collector::noteAwsRequestTime);
+    timing(timingInfo, RequestMarshallTime.name(),
+        collector::noteRequestMarshallTime);
+    timing(timingInfo, RequestSigningTime.name(),
+        collector::noteRequestSigningTime);
+    timing(timingInfo, ResponseProcessingTime.name(),
+        collector::noteResponseProcessingTime);
+  }
+
+  /**
+   * Process a timing.
+   * @param timingInfo timing info
+   * @param subMeasurementName sub measurement
+   * @param durationConsumer consumer
+   */
+  private void timing(
+      TimingInfo timingInfo,
+      String subMeasurementName,
+      Consumer<Duration> durationConsumer) {
+    TimingInfo t1 = timingInfo.getSubMeasurement(subMeasurementName);
+    if (t1 != null && t1.getTimeTakenMillisIfKnown() != null) {
+      durationConsumer.accept(Duration.ofMillis(
+          t1.getTimeTakenMillisIfKnown().longValue()));
+    }
+  }
+
+  /**
+   * Process a counter.
+   * @param timingInfo timing info
+   * @param subMeasurementName sub measurement
+   * @param consumer consumer
+   */
+  private void counter(
+      TimingInfo timingInfo,
+      String subMeasurementName,
+      LongConsumer consumer) {
+    Number n = timingInfo.getCounter(subMeasurementName);
+    if (n != null) {
+      consumer.accept(n.longValue());
+    }
+  }
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/impl/BondedS3AStatisticsContext.java

@@ -0,0 +1,234 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics.impl;
+
+import javax.annotation.Nullable;
+
+import java.time.Duration;
+
+import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.s3a.S3AInstrumentation;
+import org.apache.hadoop.fs.s3a.Statistic;
+import org.apache.hadoop.fs.s3a.s3guard.MetastoreInstrumentation;
+import org.apache.hadoop.fs.s3a.statistics.BlockOutputStreamStatistics;
+import org.apache.hadoop.fs.s3a.statistics.CommitterStatistics;
+import org.apache.hadoop.fs.s3a.statistics.DelegationTokenStatistics;
+import org.apache.hadoop.fs.s3a.statistics.S3AInputStreamStatistics;
+import org.apache.hadoop.fs.s3a.statistics.S3AMultipartUploaderStatistics;
+import org.apache.hadoop.fs.s3a.statistics.S3AStatisticsContext;
+import org.apache.hadoop.fs.s3a.statistics.StatisticsFromAwsSdk;
+
+/**
+ * An S3A statistics context which is bonded to a
+ * S3AInstrumentation instance -inevitably that of an S3AFileSystem
+ * instance.
+ * <p>
+ * An interface is used to bind to the relevant fields, rather
+ * than have them passed in the constructor because some
+ * production code, specifically, DelegateToFileSystem,
+ * patches the protected field after initialization.
+ * </p>
+ * <p>
+ * All operations are passed through directly to that class.
+ * </p>
+ * <p>
+ * If an instance of FileSystem.Statistics is passed in, it
+ * will be used whenever input stream statistics are created -
+ * However, Internally always increments the statistics in the
+ * current thread.
+ * </p>
+ * <p>
+ * As a result, cross-thread IO will under-report.
+ * </p>
+ *
+ * This is addressed through the stream statistics classes
+ * only updating the stats in the close() call. Provided
+ * they are closed in the worker thread, all stats collected in
+ * helper threads will be included.
+ */
+public class BondedS3AStatisticsContext implements S3AStatisticsContext {
+
+  /** Source of statistics services. */
+  private final S3AFSStatisticsSource statisticsSource;
+
+  /**
+   * Instantiate.
+   * @param statisticsSource integration binding
+   */
+  public BondedS3AStatisticsContext(
+      final S3AFSStatisticsSource statisticsSource) {
+    this.statisticsSource = statisticsSource;
+  }
+
+
+  /**
+   * Get the instrumentation from the FS integration.
+   * @return instrumentation instance.
+   */
+  private S3AInstrumentation getInstrumentation() {
+    return statisticsSource.getInstrumentation();
+  }
+
+  /**
+   * The filesystem statistics: know this is thread-local.
+   * @return FS statistics.
+   */
+  private FileSystem.Statistics getInstanceStatistics() {
+    return statisticsSource.getInstanceStatistics();
+  }
+
+  /**
+   * Get a MetastoreInstrumentation getInstrumentation() instance for this
+   * context.
+   * @return the S3Guard getInstrumentation() point.
+   */
+  @Override
+  public MetastoreInstrumentation getS3GuardInstrumentation() {
+    return getInstrumentation().getS3GuardInstrumentation();
+  }
+
+  /**
+   * Create a stream input statistics instance.
+   * The FileSystem.Statistics instance of the {@link #statisticsSource}
+   * is used as the reference to FileSystem statistics to update
+   * @return the new instance
+   */
+  @Override
+  public S3AInputStreamStatistics newInputStreamStatistics() {
+    return getInstrumentation().newInputStreamStatistics(
+        statisticsSource.getInstanceStatistics());
+  }
+
+  /**
+   * Create a new instance of the committer statistics.
+   * @return a new committer statistics instance
+   */
+  @Override
+  public CommitterStatistics newCommitterStatistics() {
+    return getInstrumentation().newCommitterStatistics();
+  }
+
+  /**
+   * Create a stream output statistics instance.
+   * @return the new instance
+   */
+  @Override
+  public BlockOutputStreamStatistics newOutputStreamStatistics() {
+    return getInstrumentation()
+        .newOutputStreamStatistics(getInstanceStatistics());
+  }
+
+  /**
+   * Increment a specific counter.
+   * <p>
+   * No-op if not defined.
+   * @param op operation
+   * @param count increment value
+   */
+  @Override
+  public void incrementCounter(Statistic op, long count) {
+    getInstrumentation().incrementCounter(op, count);
+  }
+
+  /**
+   * Increment a specific gauge.
+   * <p>
+   * No-op if not defined.
+   * @param op operation
+   * @param count increment value
+   * @throws ClassCastException if the metric is of the wrong type
+   */
+  @Override
+  public void incrementGauge(Statistic op, long count) {
+    getInstrumentation().incrementGauge(op, count);
+  }
+
+  /**
+   * Decrement a specific gauge.
+   * <p>
+   * No-op if not defined.
+   * @param op operation
+   * @param count increment value
+   * @throws ClassCastException if the metric is of the wrong type
+   */
+  @Override
+  public void decrementGauge(Statistic op, long count) {
+    getInstrumentation().decrementGauge(op, count);
+  }
+
+  /**
+   * Add a value to a quantiles statistic. No-op if the quantile
+   * isn't found.
+   * @param op operation to look up.
+   * @param value value to add.
+   * @throws ClassCastException if the metric is not a Quantiles.
+   */
+  @Override
+  public void addValueToQuantiles(Statistic op, long value) {
+    getInstrumentation().addValueToQuantiles(op, value);
+  }
+
+  @Override
+  public void recordDuration(final Statistic op,
+      final boolean success,
+      final Duration duration) {
+    getInstrumentation().recordDuration(op, success, duration);
+  }
+
+  /**
+   * Create a delegation token statistics instance.
+   * @return an instance of delegation token statistics
+   */
+  @Override
+  public DelegationTokenStatistics newDelegationTokenStatistics() {
+    return getInstrumentation().newDelegationTokenStatistics();
+  }
+
+  @Override
+  public StatisticsFromAwsSdk newStatisticsFromAwsSdk() {
+    return new StatisticsFromAwsSdkImpl(getInstrumentation());
+  }
+
+  @Override
+  public S3AMultipartUploaderStatistics createMultipartUploaderStatistics() {
+    return new S3AMultipartUploaderStatisticsImpl(this::incrementCounter);
+  }
+
+  /**
+   * This is the interface which an integration source must implement
+   * for the integration.
+   * Note that the FileSystem.statistics field may be null for a class;
+   */
+  public interface S3AFSStatisticsSource {
+
+    /**
+     * Get the S3A Instrumentation.
+     * @return a non-null instrumentation instance
+     */
+    S3AInstrumentation getInstrumentation();
+
+    /**
+     * Get the statistics of the FS instance, shared across all threads.
+     * @return filesystem statistics
+     */
+    @Nullable
+    FileSystem.Statistics getInstanceStatistics();
+
+  }
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/impl/CountingChangeTracker.java

@@ -0,0 +1,53 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics.impl;
+
+import java.util.concurrent.atomic.AtomicLong;
+
+import org.apache.hadoop.fs.s3a.statistics.ChangeTrackerStatistics;
+
+/**
+ * A change tracker which increments an atomic long.
+ */
+public class CountingChangeTracker implements
+    ChangeTrackerStatistics {
+
+  /**
+   * The counter which is updated on every mismatch.
+   */
+  private final AtomicLong counter;
+
+  public CountingChangeTracker(final AtomicLong counter) {
+    this.counter = counter;
+  }
+
+  public CountingChangeTracker() {
+    this(new AtomicLong());
+  }
+
+  @Override
+  public void versionMismatchError() {
+    counter.incrementAndGet();
+  }
+
+  @Override
+  public long getVersionMismatches() {
+    return counter.get();
+  }
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/impl/EmptyS3AStatisticsContext.java

@@ -0,0 +1,597 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics.impl;
+
+import java.io.IOException;
+import java.time.Duration;
+
+import org.apache.hadoop.fs.s3a.Statistic;
+import org.apache.hadoop.fs.s3a.s3guard.MetastoreInstrumentation;
+import org.apache.hadoop.fs.s3a.s3guard.MetastoreInstrumentationImpl;
+import org.apache.hadoop.fs.s3a.statistics.BlockOutputStreamStatistics;
+import org.apache.hadoop.fs.s3a.statistics.ChangeTrackerStatistics;
+import org.apache.hadoop.fs.s3a.statistics.CommitterStatistics;
+import org.apache.hadoop.fs.s3a.statistics.DelegationTokenStatistics;
+import org.apache.hadoop.fs.s3a.statistics.S3AInputStreamStatistics;
+import org.apache.hadoop.fs.s3a.statistics.S3AMultipartUploaderStatistics;
+import org.apache.hadoop.fs.s3a.statistics.S3AStatisticInterface;
+import org.apache.hadoop.fs.s3a.statistics.S3AStatisticsContext;
+import org.apache.hadoop.fs.s3a.statistics.StatisticsFromAwsSdk;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.fs.statistics.DurationTracker;
+
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.emptyStatistics;
+import static org.apache.hadoop.fs.statistics.IOStatisticsSupport.stubDurationTracker;
+
+/**
+ * Special statistics context, all of whose context operations are no-ops.
+ * All statistics instances it returns are also empty.
+ * <p>
+ * This class is here primarily to aid in testing, but it also allows for
+ * classes to require a non-empty statistics context in their constructor -yet
+ * still be instantiated without one bound to any filesystem.
+ */
+public final class EmptyS3AStatisticsContext implements S3AStatisticsContext {
+
+  public static final MetastoreInstrumentation
+      METASTORE_INSTRUMENTATION = new MetastoreInstrumentationImpl();
+
+  public static final S3AInputStreamStatistics
+      EMPTY_INPUT_STREAM_STATISTICS = new EmptyInputStreamStatistics();
+
+  public static final CommitterStatistics
+      EMPTY_COMMITTER_STATISTICS = new EmptyCommitterStatistics();
+
+  @SuppressWarnings("IOResourceOpenedButNotSafelyClosed")
+  public static final BlockOutputStreamStatistics
+      EMPTY_BLOCK_OUTPUT_STREAM_STATISTICS
+      = new EmptyBlockOutputStreamStatistics();
+
+  public static final DelegationTokenStatistics
+      EMPTY_DELEGATION_TOKEN_STATISTICS = new EmptyDelegationTokenStatistics();
+
+  public static final StatisticsFromAwsSdk
+      EMPTY_STATISTICS_FROM_AWS_SDK = new EmptyStatisticsFromAwsSdk();
+
+  @Override
+  public MetastoreInstrumentation getS3GuardInstrumentation() {
+    return METASTORE_INSTRUMENTATION;
+  }
+
+  @Override
+  public S3AInputStreamStatistics newInputStreamStatistics() {
+    return EMPTY_INPUT_STREAM_STATISTICS;
+  }
+
+  @Override
+  public CommitterStatistics newCommitterStatistics() {
+    return EMPTY_COMMITTER_STATISTICS;
+  }
+
+  @Override
+  public BlockOutputStreamStatistics newOutputStreamStatistics() {
+    return EMPTY_BLOCK_OUTPUT_STREAM_STATISTICS;
+  }
+
+  @Override
+  public DelegationTokenStatistics newDelegationTokenStatistics() {
+    return EMPTY_DELEGATION_TOKEN_STATISTICS;
+  }
+
+  @Override
+  public StatisticsFromAwsSdk newStatisticsFromAwsSdk() {
+    return EMPTY_STATISTICS_FROM_AWS_SDK;
+  }
+
+  @Override
+  public S3AMultipartUploaderStatistics createMultipartUploaderStatistics() {
+    return new EmptyMultipartUploaderStatistics();
+  }
+
+  @Override
+  public void incrementCounter(final Statistic op, final long count) {
+
+  }
+
+  @Override
+  public void incrementGauge(final Statistic op, final long count) {
+
+  }
+
+  @Override
+  public void decrementGauge(final Statistic op, final long count) {
+
+  }
+
+  @Override
+  public void addValueToQuantiles(final Statistic op, final long value) {
+
+  }
+
+  @Override
+  public void recordDuration(final Statistic op,
+      final boolean success,
+      final Duration duration) {
+
+  }
+
+  /**
+   * Base class for all the empty implementations.
+   */
+  private static class EmptyS3AStatisticImpl implements
+      S3AStatisticInterface {
+
+    /**
+     * Always return the stub duration tracker.
+     * @param key statistic key prefix
+     * @param count  #of times to increment the matching counter in this
+     * operation.
+     * @return stub tracker.
+     */
+    public DurationTracker trackDuration(String key, long count) {
+      return stubDurationTracker();
+    }
+  }
+
+  /**
+   * Input Stream statistics callbacks.
+   */
+  private static final class EmptyInputStreamStatistics
+      extends EmptyS3AStatisticImpl
+      implements S3AInputStreamStatistics {
+
+    @Override
+    public void seekBackwards(final long negativeOffset) {
+
+    }
+
+    @Override
+    public void seekForwards(final long skipped,
+        final long bytesReadInSeek) {
+
+    }
+
+    @Override
+    public long streamOpened() {
+      return 0;
+    }
+
+    @Override
+    public void streamClose(final boolean abortedConnection,
+        final long remainingInCurrentRequest) {
+
+    }
+
+    @Override
+    public void readException() {
+
+    }
+
+    @Override
+    public void bytesRead(final long bytes) {
+
+    }
+
+    @Override
+    public void readOperationStarted(final long pos, final long len) {
+
+    }
+
+    @Override
+    public void readFullyOperationStarted(final long pos, final long len) {
+
+    }
+
+    @Override
+    public void readOperationCompleted(final int requested, final int actual) {
+
+    }
+
+    @Override
+    public void close() {
+
+    }
+
+    @Override
+    public void inputPolicySet(final int updatedPolicy) {
+
+    }
+
+    @Override
+    public void unbuffered() {
+
+    }
+
+    /**
+     * Return an IO statistics instance.
+     * @return an empty IO statistics instance.
+     */
+    @Override
+    public IOStatistics getIOStatistics() {
+      return emptyStatistics();
+    }
+
+    @Override
+    public long getCloseOperations() {
+      return 0;
+    }
+
+    @Override
+    public long getClosed() {
+      return 0;
+    }
+
+    @Override
+    public long getAborted() {
+      return 0;
+    }
+
+    @Override
+    public long getForwardSeekOperations() {
+      return 0;
+    }
+
+    @Override
+    public long getBackwardSeekOperations() {
+      return 0;
+    }
+
+    @Override
+    public long getBytesRead() {
+      return 0;
+    }
+
+    @Override
+    public long getTotalBytesRead() {
+      return 0;
+    }
+
+    @Override
+    public long getBytesSkippedOnSeek() {
+      return 0;
+    }
+
+    @Override
+    public long getBytesBackwardsOnSeek() {
+      return 0;
+    }
+
+    @Override
+    public long getBytesReadInClose() {
+      return 0;
+    }
+
+    @Override
+    public long getBytesDiscardedInAbort() {
+      return 0;
+    }
+
+    @Override
+    public long getOpenOperations() {
+      return 0;
+    }
+
+    @Override
+    public long getSeekOperations() {
+      return 0;
+    }
+
+    @Override
+    public long getReadExceptions() {
+      return 0;
+    }
+
+    @Override
+    public long getReadOperations() {
+      return 0;
+    }
+
+    @Override
+    public long getReadFullyOperations() {
+      return 0;
+    }
+
+    @Override
+    public long getReadsIncomplete() {
+      return 0;
+    }
+
+    @Override
+    public long getPolicySetCount() {
+      return 0;
+    }
+
+    @Override
+    public long getVersionMismatches() {
+      return 0;
+    }
+
+    @Override
+    public long getInputPolicy() {
+      return 0;
+    }
+
+    @Override
+    public Long lookupCounterValue(final String name) {
+      return 0L;
+    }
+
+    @Override
+    public Long lookupGaugeValue(final String name) {
+      return 0L;
+    }
+
+    @Override
+    public ChangeTrackerStatistics getChangeTrackerStatistics() {
+      return new CountingChangeTracker();
+    }
+
+    @Override
+    public DurationTracker initiateGetRequest() {
+      return stubDurationTracker();
+    }
+
+  }
+
+  /**
+   * Committer statistics.
+   */
+  private static final class EmptyCommitterStatistics
+      extends EmptyS3AStatisticImpl
+      implements CommitterStatistics {
+
+    @Override
+    public void commitCreated() {
+    }
+
+    @Override
+    public void commitUploaded(final long size) {
+    }
+
+    @Override
+    public void commitCompleted(final long size) {
+    }
+
+    @Override
+    public void commitAborted() {
+    }
+
+    @Override
+    public void commitReverted() {
+    }
+
+    @Override
+    public void commitFailed() {
+    }
+
+    @Override
+    public void taskCompleted(final boolean success) {
+    }
+
+    @Override
+    public void jobCompleted(final boolean success) {
+    }
+  }
+
+  private static final class EmptyBlockOutputStreamStatistics
+      extends EmptyS3AStatisticImpl
+      implements BlockOutputStreamStatistics {
+
+    @Override
+    public void blockUploadQueued(final int blockSize) {
+    }
+
+    @Override
+    public void blockUploadStarted(final Duration timeInQueue,
+        final int blockSize) {
+    }
+
+    @Override
+    public void blockUploadCompleted(final Duration timeSinceUploadStarted,
+        final int blockSize) {
+    }
+
+    @Override
+    public void blockUploadFailed(final Duration timeSinceUploadStarted,
+        final int blockSize) {
+    }
+
+    @Override
+    public void bytesTransferred(final long byteCount) {
+    }
+
+    @Override
+    public void exceptionInMultipartComplete(final int count) {
+
+    }
+
+    @Override
+    public void exceptionInMultipartAbort() {
+    }
+
+    @Override
+    public long getBytesPendingUpload() {
+      return 0;
+    }
+
+    @Override
+    public void commitUploaded(final long size) {
+
+    }
+
+    @Override
+    public int getBlocksAllocated() {
+      return 0;
+    }
+
+    @Override
+    public int getBlocksReleased() {
+      return 0;
+    }
+
+    @Override
+    public int getBlocksActivelyAllocated() {
+      return 0;
+    }
+
+    @Override
+    public IOStatistics getIOStatistics() {
+      return emptyStatistics();
+    }
+
+    @Override
+    public void blockAllocated() {
+    }
+
+    @Override
+    public void blockReleased() {
+    }
+
+    @Override
+    public void writeBytes(final long count) {
+    }
+
+    @Override
+    public long getBytesWritten() {
+      return 0;
+    }
+
+    @Override
+    public Long lookupCounterValue(final String name) {
+      return 0L;
+    }
+
+    @Override
+    public Long lookupGaugeValue(final String name) {
+      return 0L;
+    }
+
+    @Override
+    public void close() throws IOException {
+    }
+
+  }
+
+  /**
+   * Delegation Token Statistics.
+   */
+  private static final class EmptyDelegationTokenStatistics
+      extends EmptyS3AStatisticImpl
+      implements DelegationTokenStatistics {
+
+    @Override
+    public void tokenIssued() {
+
+    }
+  }
+
+  /**
+   * AWS SDK Callbacks.
+   */
+  private static final class EmptyStatisticsFromAwsSdk
+      implements StatisticsFromAwsSdk {
+
+    @Override
+    public void updateAwsRequestCount(final long longValue) {
+
+    }
+
+    @Override
+    public void updateAwsRetryCount(final long longValue) {
+
+    }
+
+    @Override
+    public void updateAwsThrottleExceptionsCount(final long longValue) {
+
+    }
+
+    @Override
+    public void noteAwsRequestTime(final Duration ofMillis) {
+
+    }
+
+    @Override
+    public void noteAwsClientExecuteTime(final Duration ofMillis) {
+
+    }
+
+    @Override
+    public void noteRequestMarshallTime(final Duration duration) {
+
+    }
+
+    @Override
+    public void noteRequestSigningTime(final Duration duration) {
+
+    }
+
+    @Override
+    public void noteResponseProcessingTime(final Duration duration) {
+
+    }
+  }
+
+  /**
+   * Multipart Uploader.
+   */
+  public static final class EmptyMultipartUploaderStatistics
+      implements S3AMultipartUploaderStatistics {
+
+    @Override
+    public void instantiated() {
+
+    }
+
+    @Override
+    public void uploadStarted() {
+
+    }
+
+    @Override
+    public void partPut(final long lengthInBytes) {
+
+    }
+
+    @Override
+    public void uploadCompleted() {
+
+    }
+
+    @Override
+    public void uploadAborted() {
+
+    }
+
+    @Override
+    public void abortUploadsUnderPathInvoked() {
+
+    }
+
+    @Override
+    public void close() throws IOException {
+
+    }
+
+    @Override
+    public DurationTracker trackDuration(final String key, final long count) {
+      return stubDurationTracker();
+    }
+  }
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/impl/statistics/S3AMultipartUploaderStatisticsImpl.java → hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/impl/S3AMultipartUploaderStatisticsImpl.java

@@ -16,30 +16,42 @@
  * limitations under the License.
  */
 
-package org.apache.hadoop.fs.s3a.impl.statistics;
+package org.apache.hadoop.fs.s3a.statistics.impl;
 
 
 import java.io.IOException;
+import java.util.Objects;
 import java.util.function.BiConsumer;
 
 import org.apache.hadoop.fs.s3a.Statistic;
+import org.apache.hadoop.fs.s3a.statistics.S3AMultipartUploaderStatistics;
+import org.apache.hadoop.fs.statistics.impl.IOStatisticsStore;
 
-import static org.apache.hadoop.fs.s3a.Statistic.MULTIPART_UPLOAD_ABORT_UNDER_PATH_INVOKED;
-import static org.apache.hadoop.fs.s3a.Statistic.MULTIPART_INSTANTIATED;
-import static org.apache.hadoop.fs.s3a.Statistic.MULTIPART_PART_PUT;
-import static org.apache.hadoop.fs.s3a.Statistic.MULTIPART_PART_PUT_BYTES;
 import static org.apache.hadoop.fs.s3a.Statistic.MULTIPART_UPLOAD_ABORTED;
+import static org.apache.hadoop.fs.s3a.Statistic.MULTIPART_UPLOAD_ABORT_UNDER_PATH_INVOKED;
 import static org.apache.hadoop.fs.s3a.Statistic.MULTIPART_UPLOAD_COMPLETED;
+import static org.apache.hadoop.fs.s3a.Statistic.MULTIPART_UPLOAD_INSTANTIATED;
+import static org.apache.hadoop.fs.s3a.Statistic.MULTIPART_UPLOAD_PART_PUT;
+import static org.apache.hadoop.fs.s3a.Statistic.MULTIPART_UPLOAD_PART_PUT_BYTES;
 import static org.apache.hadoop.fs.s3a.Statistic.MULTIPART_UPLOAD_STARTED;
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.iostatisticsStore;
 
 /**
  * Implementation of the uploader statistics.
+ * <p>
  * This takes a function to update some counter and will update
  * this value when things change, so it can be bonded to arbitrary
  * statistic collectors.
+ * </p>
+ * <p>
+ * Internally it builds a map of the relevant multipart statistics,
+ * increments as appropriate and serves this data back through
+ * the {@code IOStatisticsSource} API.
+ * </p>
  */
-public final class S3AMultipartUploaderStatisticsImpl implements
-    S3AMultipartUploaderStatistics {
+public final class S3AMultipartUploaderStatisticsImpl
+    extends AbstractS3AStatisticsSource
+    implements S3AMultipartUploaderStatistics {
 
   /**
    * The operation to increment a counter/statistic by a value.
@@ -53,16 +65,28 @@ public final class S3AMultipartUploaderStatisticsImpl implements
    */
   public S3AMultipartUploaderStatisticsImpl(
       final BiConsumer<Statistic, Long> incrementCallback) {
-    this.incrementCallback = incrementCallback;
+    this.incrementCallback = Objects.requireNonNull(incrementCallback);
+    IOStatisticsStore st = iostatisticsStore()
+        .withCounters(
+            MULTIPART_UPLOAD_INSTANTIATED.getSymbol(),
+            MULTIPART_UPLOAD_PART_PUT.getSymbol(),
+            MULTIPART_UPLOAD_PART_PUT_BYTES.getSymbol(),
+            MULTIPART_UPLOAD_ABORTED.getSymbol(),
+            MULTIPART_UPLOAD_ABORT_UNDER_PATH_INVOKED.getSymbol(),
+            MULTIPART_UPLOAD_COMPLETED.getSymbol(),
+            MULTIPART_UPLOAD_STARTED.getSymbol())
+        .build();
+    setIOStatistics(st);
   }
 
   private void inc(Statistic op, long count) {
     incrementCallback.accept(op, count);
+    incCounter(op.getSymbol(), count);
   }
 
   @Override
   public void instantiated() {
-    inc(MULTIPART_INSTANTIATED, 1);
+    inc(MULTIPART_UPLOAD_INSTANTIATED, 1);
   }
 
   @Override
@@ -72,8 +96,8 @@ public final class S3AMultipartUploaderStatisticsImpl implements
 
   @Override
   public void partPut(final long lengthInBytes) {
-    inc(MULTIPART_PART_PUT, 1);
-    inc(MULTIPART_PART_PUT_BYTES, lengthInBytes);
+    inc(MULTIPART_UPLOAD_PART_PUT, 1);
+    inc(MULTIPART_UPLOAD_PART_PUT_BYTES, lengthInBytes);
   }
 
   @Override

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/impl/StatisticsFromAwsSdkImpl.java

@@ -0,0 +1,88 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.statistics.impl;
+
+import java.time.Duration;
+
+import org.apache.hadoop.fs.s3a.statistics.CountersAndGauges;
+import org.apache.hadoop.fs.s3a.statistics.StatisticsFromAwsSdk;
+
+import static org.apache.hadoop.fs.s3a.Statistic.STORE_IO_REQUEST;
+import static org.apache.hadoop.fs.s3a.Statistic.STORE_IO_RETRY;
+import static org.apache.hadoop.fs.s3a.Statistic.STORE_IO_THROTTLED;
+import static org.apache.hadoop.fs.s3a.Statistic.STORE_IO_THROTTLE_RATE;
+
+/**
+ * Hook up AWS SDK Statistics to the S3 counters.
+ * <p>
+ * Durations are not currently being used; that could be
+ * changed in future once an effective strategy for reporting
+ * them is determined.
+ */
+public final class StatisticsFromAwsSdkImpl implements
+    StatisticsFromAwsSdk {
+
+  private final CountersAndGauges countersAndGauges;
+
+  public StatisticsFromAwsSdkImpl(
+      final CountersAndGauges countersAndGauges) {
+    this.countersAndGauges = countersAndGauges;
+  }
+
+  @Override
+  public void updateAwsRequestCount(final long count) {
+    countersAndGauges.incrementCounter(STORE_IO_REQUEST, count);
+  }
+
+  @Override
+  public void updateAwsRetryCount(final long count) {
+    countersAndGauges.incrementCounter(STORE_IO_RETRY, count);
+  }
+
+  @Override
+  public void updateAwsThrottleExceptionsCount(final long count) {
+    countersAndGauges.incrementCounter(STORE_IO_THROTTLED, count);
+    countersAndGauges.addValueToQuantiles(STORE_IO_THROTTLE_RATE, count);
+  }
+
+  @Override
+  public void noteAwsRequestTime(final Duration duration) {
+
+  }
+
+  @Override
+  public void noteAwsClientExecuteTime(final Duration duration) {
+
+  }
+
+  @Override
+  public void noteRequestMarshallTime(final Duration duration) {
+
+  }
+
+  @Override
+  public void noteRequestSigningTime(final Duration duration) {
+
+  }
+
+  @Override
+  public void noteResponseProcessingTime(final Duration duration) {
+
+  }
+}

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/impl/package-info.java

@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Statistics collection for the S3A connector: implementation.
+ * Not for use by anything outside the hadoop-aws source tree.
+ */
+
+@InterfaceAudience.Private
+@InterfaceStability.Unstable
+package org.apache.hadoop.fs.s3a.statistics.impl;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.classification.InterfaceStability;

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/statistics/package-info.java

@@ -0,0 +1,31 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Statistics collection for the S3A connector: interfaces.
+ * This is private, though there's a risk that some extension
+ * points (delegation tokens?) may need access to the internal
+ * API. Hence the split packaging...with a java 9 module, the
+ * implementation classes would be declared internal.
+ */
+@InterfaceAudience.Private
+@InterfaceStability.Unstable
+package org.apache.hadoop.fs.s3a.statistics;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.classification.InterfaceStability;

hadoop-tools/hadoop-aws/src/main/java/org/apache/hadoop/fs/s3a/tools/MarkerTool.java

@@ -65,6 +65,7 @@ import static org.apache.hadoop.fs.s3a.Constants.AUTHORITATIVE_PATH;
 import static org.apache.hadoop.fs.s3a.Constants.BULK_DELETE_PAGE_SIZE;
 import static org.apache.hadoop.fs.s3a.Constants.BULK_DELETE_PAGE_SIZE_DEFAULT;
 import static org.apache.hadoop.fs.s3a.Invoker.once;
+import static org.apache.hadoop.fs.statistics.IOStatisticsLogging.ioStatisticsSourceToString;
 import static org.apache.hadoop.service.launcher.LauncherExitCodes.EXIT_INTERRUPTED;
 import static org.apache.hadoop.service.launcher.LauncherExitCodes.EXIT_NOT_ACCEPTABLE;
 import static org.apache.hadoop.service.launcher.LauncherExitCodes.EXIT_NOT_FOUND;
@@ -672,6 +673,7 @@ public final class MarkerTool extends S3GuardTool {
       final int limit) throws IOException {
 
     int count = 0;
+    boolean result = true;
     RemoteIterator<S3AFileStatus> listing = operations
         .listObjects(path, storeContext.pathToKey(path));
     while (listing.hasNext()) {
@@ -700,10 +702,16 @@ public final class MarkerTool extends S3GuardTool {
       if (limit > 0 && count >= limit) {
         println(out, "Limit of scan reached - %,d object%s",
             limit, suffix(limit));
-        return false;
+        result = false;
+        break;
       }
     }
-    return true;
+    LOG.debug("Listing summary {}", listing);
+    if (verbose) {
+      println(out, "%nListing statistics:%n  %s%n",
+          ioStatisticsSourceToString(listing));
+    }
+    return result;
   }
 
   /**

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/contract/s3a/ITestS3AContractDistCp.java

@@ -79,15 +79,15 @@ public class ITestS3AContractDistCp extends AbstractContractDistCpTest {
 
   @Override
   public void testDirectWrite() throws Exception {
-    resetStorageStatistics();
+    final long renames = getRenameOperationCount();
     super.testDirectWrite();
     assertEquals("Expected no renames for a direct write distcp", 0L,
-        getRenameOperationCount());
+        getRenameOperationCount() - renames);
   }
 
   @Override
   public void testNonDirectWrite() throws Exception {
-    resetStorageStatistics();
+    final long renames = getRenameOperationCount();
     try {
       super.testNonDirectWrite();
     } catch (FileNotFoundException e) {
@@ -96,11 +96,7 @@ public class ITestS3AContractDistCp extends AbstractContractDistCpTest {
       // S3Guard is not enabled
     }
     assertEquals("Expected 2 renames for a non-direct write distcp", 2L,
-        getRenameOperationCount());
-  }
-
-  private void resetStorageStatistics() {
-    getFileSystem().getStorageStatistics().reset();
+        getRenameOperationCount() - renames);
   }
 
   private long getRenameOperationCount() {

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/AbstractS3ATestBase.java

@@ -26,7 +26,10 @@ import org.apache.hadoop.fs.contract.AbstractFSContractTestBase;
 import org.apache.hadoop.fs.contract.ContractTestUtils;
 import org.apache.hadoop.fs.contract.s3a.S3AContract;
 import org.apache.hadoop.fs.s3a.tools.MarkerTool;
+import org.apache.hadoop.fs.statistics.IOStatisticsSnapshot;
 import org.apache.hadoop.io.IOUtils;
+
+import org.junit.AfterClass;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -39,6 +42,8 @@ import static org.apache.hadoop.fs.s3a.S3ATestUtils.getTestDynamoTablePrefix;
 import static org.apache.hadoop.fs.s3a.S3ATestUtils.getTestPropertyBool;
 import static org.apache.hadoop.fs.s3a.S3AUtils.E_FS_CLOSED;
 import static org.apache.hadoop.fs.s3a.tools.MarkerTool.UNLIMITED_LISTING;
+import static org.apache.hadoop.fs.statistics.IOStatisticsLogging.ioStatisticsToPrettyString;
+import static org.apache.hadoop.fs.statistics.IOStatisticsSupport.snapshotIOStatistics;
 
 /**
  * An extension of the contract test base set up for S3A tests.
@@ -48,6 +53,12 @@ public abstract class AbstractS3ATestBase extends AbstractFSContractTestBase
   protected static final Logger LOG =
       LoggerFactory.getLogger(AbstractS3ATestBase.class);
 
+  /**
+   * FileSystem statistics are collected across every test case.
+   */
+  protected static final IOStatisticsSnapshot FILESYSTEM_IOSTATS =
+      snapshotIOStatistics();
+
   @Override
   protected AbstractFSContract createContract(Configuration conf) {
     return new S3AContract(conf, false);
@@ -73,10 +84,22 @@ public abstract class AbstractS3ATestBase extends AbstractFSContractTestBase
     maybeAuditTestPath();
 
     super.teardown();
+    if (getFileSystem() != null) {
+      FILESYSTEM_IOSTATS.aggregate(getFileSystem().getIOStatistics());
+    }
     describe("closing file system");
     IOUtils.closeStream(getFileSystem());
   }
 
+  /**
+   * Dump the filesystem statistics after the class.
+   */
+  @AfterClass
+  public static void dumpFileSystemIOStatistics() {
+    LOG.info("Aggregate FileSystem Statistics {}",
+        ioStatisticsToPrettyString(FILESYSTEM_IOSTATS));
+  }
+
   /**
    * Audit the FS under {@link #methodPath()} if
    * the test option {@link #DIRECTORY_MARKER_AUDIT} is

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/ITestLocatedFileStatusFetcher.java

@@ -18,23 +18,287 @@
 
 package org.apache.hadoop.fs.s3a;
 
+import java.nio.charset.StandardCharsets;
+import java.util.Arrays;
+import java.util.Collection;
+
+import org.assertj.core.api.Assertions;
 import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileStatus;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.fs.PathFilter;
+import org.apache.hadoop.fs.s3a.auth.ITestRestrictedReadAccess;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.mapred.LocatedFileStatusFetcher;
+
+import static org.apache.hadoop.fs.contract.ContractTestUtils.createFile;
+import static org.apache.hadoop.fs.contract.ContractTestUtils.touch;
+import static org.apache.hadoop.fs.s3a.Constants.AUTHORITATIVE_PATH;
+import static org.apache.hadoop.fs.s3a.Constants.METADATASTORE_AUTHORITATIVE;
+import static org.apache.hadoop.fs.s3a.Constants.S3_METADATA_STORE_IMPL;
+import static org.apache.hadoop.fs.s3a.S3ATestUtils.disableFilesystemCaching;
+import static org.apache.hadoop.fs.s3a.S3ATestUtils.getTestBucketName;
+import static org.apache.hadoop.fs.s3a.S3ATestUtils.removeBaseAndBucketOverrides;
+import static org.apache.hadoop.fs.s3a.S3ATestUtils.removeBucketOverrides;
+import static org.apache.hadoop.fs.statistics.IOStatisticAssertions.assertThatStatisticCounter;
+import static org.apache.hadoop.fs.statistics.IOStatisticAssertions.extractStatistics;
+import static org.apache.hadoop.fs.statistics.StoreStatisticNames.OBJECT_LIST_REQUEST;
+import static org.apache.hadoop.mapreduce.lib.input.FileInputFormat.LIST_STATUS_NUM_THREADS;
+
 /**
  * Test the LocatedFileStatusFetcher can do.
  * This is related to HADOOP-16458.
  * There's basic tests in ITestS3AFSMainOperations; this
  * is see if we can create better corner cases.
+ * <p></p>
+ * Much of the class is based on tests in {@link ITestRestrictedReadAccess},
+ * but whereas that tests failure paths, this looks at the performance
+ * of successful invocations.
  */
+@RunWith(Parameterized.class)
 public class ITestLocatedFileStatusFetcher extends AbstractS3ATestBase {
 
   private static final Logger LOG =
       LoggerFactory.getLogger(ITestLocatedFileStatusFetcher.class);
 
+
+  /**
+   * Parameterization.
+   */
+  @Parameterized.Parameters(name = "{0}")
+  public static Collection<Object[]> params() {
+    return Arrays.asList(new Object[][]{
+        {"raw", false},
+        {"nonauth", true}
+    });
+  }
+
+  /** Filter to select everything. */
+  private static final PathFilter EVERYTHING = t -> true;
+
+  /** Filter to select .txt files. */
+  private static final PathFilter TEXT_FILE =
+      path -> path.toUri().toString().endsWith(".txt");
+
+  /** The same path filter used in FileInputFormat. */
+  private static final PathFilter HIDDEN_FILE_FILTER =
+      (p) -> {
+        String n = p.getName();
+        return !n.startsWith("_") && !n.startsWith(".");
+      };
+
+  /**
+   * Text found in LocatedFileStatusFetcher exception when the glob
+   * returned "null".
+   */
+  private static final String DOES_NOT_EXIST = "does not exist";
+
+  /**
+   * Text found in LocatedFileStatusFetcher exception when
+   * the glob returned an empty list.
+   */
+  private static final String MATCHES_0_FILES = "matches 0 files";
+
+  /**
+   * Text used in files.
+   */
+  public static final byte[] HELLO = "hello".getBytes(StandardCharsets.UTF_8);
+
+  /**
+   * How many list calls are expected in a run which collects them: {@value}.
+   */
+  private static final int EXPECTED_LIST_COUNT = 4;
+
+  private final String name;
+
+  private final boolean s3guard;
+
+  private Path basePath;
+
+  private Path emptyDir;
+
+  private Path emptyFile;
+
+  private Path subDir;
+
+  private Path subdirFile;
+
+  private Path subDir2;
+
+  private Path subdir2File1;
+
+  private Path subdir2File2;
+
+  private Configuration listConfig;
+
+  public ITestLocatedFileStatusFetcher(final String name,
+      final boolean s3guard) {
+    this.name = name;
+    this.s3guard = s3guard;
+  }
+
+  @Override
+  public Configuration createConfiguration() {
+    Configuration conf = super.createConfiguration();
+    String bucketName = getTestBucketName(conf);
+
+    removeBaseAndBucketOverrides(bucketName, conf,
+        METADATASTORE_AUTHORITATIVE,
+        AUTHORITATIVE_PATH);
+    removeBucketOverrides(bucketName, conf,
+        S3_METADATA_STORE_IMPL);
+    if (!s3guard) {
+      removeBaseAndBucketOverrides(bucketName, conf,
+          S3_METADATA_STORE_IMPL);
+    }
+    conf.setBoolean(METADATASTORE_AUTHORITATIVE, false);
+    disableFilesystemCaching(conf);
+    return conf;
+  }
+  @Override
+  public void setup() throws Exception {
+    super.setup();
+    S3AFileSystem fs
+        = getFileSystem();
+    // avoiding the parameterization to steer clear of accidentally creating
+    // patterns; a timestamp is used to ensure tombstones from previous runs
+    // do not interfere
+    basePath = path("ITestLocatedFileStatusFetcher-" + name
+        + "-" + System.currentTimeMillis() / 1000);
+
+    // define the paths and create them.
+    describe("Creating test directories and files");
+
+    // an empty directory directory under the noReadDir
+    emptyDir = new Path(basePath, "emptyDir");
+    fs.mkdirs(emptyDir);
+
+    // an empty file directory under the noReadDir
+    emptyFile = new Path(basePath, "emptyFile.txt");
+    touch(fs, emptyFile);
+
+    // a subdirectory
+    subDir = new Path(basePath, "subDir");
+
+    // and a file in that subdirectory
+    subdirFile = new Path(subDir, "subdirFile.txt");
+    createFile(fs, subdirFile, true, HELLO);
+    subDir2 = new Path(subDir, "subDir2");
+    subdir2File1 = new Path(subDir2, "subdir2File1.txt");
+    subdir2File2 = new Path(subDir2, "subdir2File2.txt");
+    createFile(fs, subdir2File1, true, HELLO);
+    createFile(fs, subdir2File2, true, HELLO);
+    listConfig = new Configuration(getConfiguration());
+  }
+
+
+  /**
+   * Assert that the fetcher stats logs the expected number of calls.
+   * @param fetcher fetcher
+   * @param expectedListCount expected number of list calls
+   */
+  private void assertListCount(final LocatedFileStatusFetcher fetcher,
+      final int expectedListCount) {
+    IOStatistics iostats = extractStatistics(fetcher);
+    LOG.info("Statistics of fetcher: {}", iostats);
+    assertThatStatisticCounter(iostats,
+        OBJECT_LIST_REQUEST)
+        .describedAs("stats of %s", iostats)
+        .isEqualTo(expectedListCount);
+  }
+
+  /**
+   * Run a located file status fetcher against the directory tree.
+   */
   @Test
-  public void testGlobScan() throws Throwable {
+  public void testSingleThreadedLocatedFileStatus() throws Throwable {
+
+    describe("LocatedFileStatusFetcher operations");
+    // use the same filter as FileInputFormat; single thread.
 
+    listConfig.setInt(LIST_STATUS_NUM_THREADS, 1);
+    LocatedFileStatusFetcher fetcher =
+        new LocatedFileStatusFetcher(
+            listConfig,
+            new Path[]{basePath},
+            true,
+            HIDDEN_FILE_FILTER,
+            true);
+    Iterable<FileStatus> stats = fetcher.getFileStatuses();
+    Assertions.assertThat(stats)
+        .describedAs("result of located scan")
+        .flatExtracting(FileStatus::getPath)
+        .containsExactlyInAnyOrder(
+            emptyFile,
+            subdirFile,
+            subdir2File1,
+            subdir2File2);
+    assertListCount(fetcher, EXPECTED_LIST_COUNT);
   }
+
+  /**
+   * Run a located file status fetcher against the directory tree.
+   */
+  @Test
+  public void testLocatedFileStatusFourThreads() throws Throwable {
+
+    // four threads and the text filter.
+    int threads = 4;
+    describe("LocatedFileStatusFetcher with %d", threads);
+    listConfig.setInt(LIST_STATUS_NUM_THREADS, threads);
+    LocatedFileStatusFetcher fetcher =
+        new LocatedFileStatusFetcher(
+            listConfig,
+            new Path[]{basePath},
+            true,
+            EVERYTHING,
+            true);
+    Iterable<FileStatus> stats = fetcher.getFileStatuses();
+    IOStatistics iostats = extractStatistics(fetcher);
+    LOG.info("Statistics of fetcher: {}", iostats);
+    Assertions.assertThat(stats)
+        .describedAs("result of located scan")
+        .isNotNull()
+        .flatExtracting(FileStatus::getPath)
+        .containsExactlyInAnyOrder(
+            emptyFile,
+            subdirFile,
+            subdir2File1,
+            subdir2File2);
+    assertListCount(fetcher, EXPECTED_LIST_COUNT);
+  }
+
+  /**
+   * Run a located file status fetcher against a file.
+   */
+  @Test
+  public void testLocatedFileStatusScanFile() throws Throwable {
+    // pass in a file as the base of the scan.
+    describe("LocatedFileStatusFetcher with file %s", subdirFile);
+    listConfig.setInt(LIST_STATUS_NUM_THREADS, 16);
+    LocatedFileStatusFetcher fetcher
+        = new LocatedFileStatusFetcher(
+        listConfig,
+        new Path[]{subdirFile},
+        true,
+        TEXT_FILE,
+        true);
+    Iterable<FileStatus> stats = fetcher.getFileStatuses();
+    Assertions.assertThat(stats)
+        .describedAs("result of located scan")
+        .isNotNull()
+        .flatExtracting(FileStatus::getPath)
+        .containsExactly(subdirFile);
+    IOStatistics ioStatistics = fetcher.getIOStatistics();
+    Assertions.assertThat(ioStatistics)
+        .describedAs("IO statistics of %s", fetcher)
+        .isNull();
+  }
+
 }

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/ITestS3ABlockOutputArray.java

@@ -22,6 +22,7 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.contract.ContractTestUtils;
+import org.apache.hadoop.fs.s3a.statistics.BlockOutputStreamStatistics;
 import org.apache.hadoop.io.IOUtils;
 
 import org.junit.BeforeClass;
@@ -94,16 +95,16 @@ public class ITestS3ABlockOutputArray extends AbstractS3ATestBase {
     Path dest = path("testBlocksClosed");
     describe(" testBlocksClosed");
     FSDataOutputStream stream = getFileSystem().create(dest, true);
-    S3AInstrumentation.OutputStreamStatistics statistics
+    BlockOutputStreamStatistics statistics
         = S3ATestUtils.getOutputStreamStatistics(stream);
     byte[] data = ContractTestUtils.dataset(16, 'a', 26);
     stream.write(data);
     LOG.info("closing output stream");
     stream.close();
     assertEquals("total allocated blocks in " + statistics,
-        1, statistics.blocksAllocated());
+        1, statistics.getBlocksAllocated());
     assertEquals("actively allocated blocks in " + statistics,
-        0, statistics.blocksActivelyAllocated());
+        0, statistics.getBlocksActivelyAllocated());
     LOG.info("end of test case");
   }
 
@@ -129,7 +130,7 @@ public class ITestS3ABlockOutputArray extends AbstractS3ATestBase {
       throws Exception {
     S3AInstrumentation instrumentation =
         new S3AInstrumentation(new URI("s3a://example"));
-    S3AInstrumentation.OutputStreamStatistics outstats
+    BlockOutputStreamStatistics outstats
         = instrumentation.newOutputStreamStatistics(null);
     S3ADataBlocks.DataBlock block = factory.create(1, BLOCK_SIZE, outstats);
     block.write(dataset, 0, dataset.length);

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/ITestS3AMetrics.java

@@ -21,11 +21,15 @@ package org.apache.hadoop.fs.s3a;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.contract.ContractTestUtils;
 import org.apache.hadoop.metrics2.lib.MutableCounterLong;
+
+import org.assertj.core.api.Assertions;
 import org.junit.Test;
 
 import java.io.IOException;
 import java.io.InputStream;
 
+import static org.apache.hadoop.fs.statistics.IOStatisticsLogging.ioStatisticsSourceToString;
+
 /**
  * Test s3a performance metrics register and output.
  */
@@ -51,17 +55,34 @@ public class ITestS3AMetrics extends AbstractS3ATestBase {
     Path file = path("testStreamStatistics");
     byte[] data = "abcdefghijklmnopqrstuvwxyz".getBytes();
     ContractTestUtils.createFile(fs, file, false, data);
-
-    try (InputStream inputStream = fs.open(file)) {
+    InputStream inputStream = fs.open(file);
+    try {
       while (inputStream.read(data) != -1) {
         LOG.debug("Read batch of data from input stream...");
       }
+      LOG.info("Final stream statistics: {}",
+          ioStatisticsSourceToString(inputStream));
+    } finally {
+      // this is not try-with-resources only to aid debugging
+      inputStream.close();
     }
 
+    final String statName = Statistic.STREAM_READ_BYTES.getSymbol();
+
+    final S3AInstrumentation instrumentation = fs.getInstrumentation();
+
+    final long counterValue = instrumentation.getCounterValue(statName);
+
+    final int expectedBytesRead = 26;
+    Assertions.assertThat(counterValue)
+        .describedAs("Counter %s from instrumentation %s",
+            statName, instrumentation)
+        .isEqualTo(expectedBytesRead);
     MutableCounterLong read = (MutableCounterLong)
-        fs.getInstrumentation().getRegistry()
-        .get(Statistic.STREAM_SEEK_BYTES_READ.getSymbol());
-    assertEquals("Stream statistics were not merged", 26, read.value());
+        instrumentation.getRegistry()
+        .get(statName);
+    assertEquals("Stream statistics were not merged", expectedBytesRead,
+        read.value());
   }
 
 

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/ITestS3AMiscOperations.java

@@ -276,8 +276,14 @@ public class ITestS3AMiscOperations extends AbstractS3ATestBase {
     }
   }
 
+  @Test
+  public void testS3AIOStatisticsUninitialized() throws Throwable {
+    try (S3AFileSystem fs = new S3AFileSystem()) {
+      fs.getIOStatistics();
+    }
+
+  }
   /**
-<<<<<<< ours
    * Verify that paths with a trailing "/" are fixed up.
    */
   @Test

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/ITestS3AUnbuffer.java

@@ -21,13 +21,23 @@ package org.apache.hadoop.fs.s3a;
 import org.apache.hadoop.fs.FSDataInputStream;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.contract.ContractTestUtils;
+import org.apache.hadoop.fs.s3a.statistics.S3AInputStreamStatistics;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.fs.statistics.IOStatisticsSnapshot;
+import org.apache.hadoop.fs.statistics.StoreStatisticNames;
+import org.apache.hadoop.fs.statistics.StreamStatisticNames;
 import org.apache.hadoop.io.IOUtils;
 
+import org.assertj.core.api.Assertions;
 import org.junit.Test;
 
 import java.io.IOException;
 
-import static org.apache.hadoop.fs.s3a.Statistic.STREAM_SEEK_BYTES_READ;
+import static org.apache.hadoop.fs.s3a.Statistic.STREAM_READ_BYTES;
+import static org.apache.hadoop.fs.s3a.Statistic.STREAM_READ_BYTES_READ_CLOSE;
+import static org.apache.hadoop.fs.s3a.Statistic.STREAM_READ_TOTAL_BYTES;
+import static org.apache.hadoop.fs.statistics.IOStatisticAssertions.verifyStatisticCounterValue;
+import static org.apache.hadoop.fs.statistics.IOStatisticsLogging.demandStringifyIOStatisticsSource;
 
 /**
  * Integration test for calling
@@ -40,6 +50,8 @@ import static org.apache.hadoop.fs.s3a.Statistic.STREAM_SEEK_BYTES_READ;
  */
 public class ITestS3AUnbuffer extends AbstractS3ATestBase {
 
+  public static final int FILE_LENGTH = 16;
+
   private Path dest;
 
   @Override
@@ -48,7 +60,7 @@ public class ITestS3AUnbuffer extends AbstractS3ATestBase {
     dest = path("ITestS3AUnbuffer");
     describe("ITestS3AUnbuffer");
 
-    byte[] data = ContractTestUtils.dataset(16, 'a', 26);
+    byte[] data = ContractTestUtils.dataset(FILE_LENGTH, 'a', 26);
     ContractTestUtils.writeDataset(getFileSystem(), dest, data, data.length,
             16, true);
   }
@@ -57,13 +69,41 @@ public class ITestS3AUnbuffer extends AbstractS3ATestBase {
   public void testUnbuffer() throws IOException {
     describe("testUnbuffer");
 
+    IOStatisticsSnapshot iostats = new IOStatisticsSnapshot();
     // Open file, read half the data, and then call unbuffer
     try (FSDataInputStream inputStream = getFileSystem().open(dest)) {
       assertTrue(inputStream.getWrappedStream() instanceof S3AInputStream);
-      readAndAssertBytesRead(inputStream, 8);
+      int bytesToRead = 8;
+      readAndAssertBytesRead(inputStream, bytesToRead);
       assertTrue(isObjectStreamOpen(inputStream));
+      assertTrue("No IOstatistics from " + inputStream,
+          iostats.aggregate(inputStream.getIOStatistics()));
+      verifyStatisticCounterValue(iostats,
+          StreamStatisticNames.STREAM_READ_BYTES,
+          bytesToRead);
+      verifyStatisticCounterValue(iostats,
+          StoreStatisticNames.ACTION_HTTP_GET_REQUEST,
+          1);
+
+      // do the unbuffering
       inputStream.unbuffer();
 
+      // audit the updated statistics
+      IOStatistics st2 = inputStream.getIOStatistics();
+
+      // the unbuffered operation must be tracked
+      verifyStatisticCounterValue(st2,
+          StreamStatisticNames.STREAM_READ_UNBUFFERED,
+          1);
+
+      // all other counter values consistent.
+      verifyStatisticCounterValue(st2,
+          StreamStatisticNames.STREAM_READ_BYTES,
+          bytesToRead);
+      verifyStatisticCounterValue(st2,
+          StoreStatisticNames.ACTION_HTTP_GET_REQUEST,
+          1);
+
       // Check the the wrapped stream is closed
       assertFalse(isObjectStreamOpen(inputStream));
     }
@@ -71,7 +111,7 @@ public class ITestS3AUnbuffer extends AbstractS3ATestBase {
 
   /**
    * Test that calling {@link S3AInputStream#unbuffer()} merges a stream's
-   * {@link org.apache.hadoop.fs.s3a.S3AInstrumentation.InputStreamStatistics}
+   * {@code InputStreamStatistics}
    * into the {@link S3AFileSystem}'s {@link S3AInstrumentation} instance.
    */
   @Test
@@ -79,36 +119,73 @@ public class ITestS3AUnbuffer extends AbstractS3ATestBase {
     describe("testUnbufferStreamStatistics");
 
     // Validate bytesRead is updated correctly
+    S3AFileSystem fs = getFileSystem();
     S3ATestUtils.MetricDiff bytesRead = new S3ATestUtils.MetricDiff(
-            getFileSystem(), STREAM_SEEK_BYTES_READ);
+        fs, STREAM_READ_BYTES);
+    S3ATestUtils.MetricDiff totalBytesRead = new S3ATestUtils.MetricDiff(
+        fs, STREAM_READ_TOTAL_BYTES);
+    S3ATestUtils.MetricDiff bytesReadInClose = new S3ATestUtils.MetricDiff(
+        fs, STREAM_READ_BYTES_READ_CLOSE);
 
     // Open file, read half the data, and then call unbuffer
     FSDataInputStream inputStream = null;
+    int firstBytesToRead = 8;
+
+    int secondBytesToRead = 1;
+    long expectedFinalBytesRead;
+    long expectedTotalBytesRead;
+
+    Object streamStatsStr;
     try {
-      inputStream = getFileSystem().open(dest);
+      inputStream = fs.open(dest);
+      streamStatsStr = demandStringifyIOStatisticsSource(inputStream);
 
-      readAndAssertBytesRead(inputStream, 8);
+      LOG.info("initial stream statistics {}", streamStatsStr);
+      readAndAssertBytesRead(inputStream, firstBytesToRead);
+      LOG.info("stream statistics after read {}", streamStatsStr);
       inputStream.unbuffer();
 
       // Validate that calling unbuffer updates the input stream statistics
-      bytesRead.assertDiffEquals(8);
+      bytesRead.assertDiffEquals(firstBytesToRead);
+      final long bytesInUnbuffer = bytesReadInClose.diff();
+      totalBytesRead.assertDiffEquals(firstBytesToRead + bytesInUnbuffer);
 
       // Validate that calling unbuffer twice in a row updates the statistics
       // correctly
-      readAndAssertBytesRead(inputStream, 4);
+      bytesReadInClose.reset();
+      bytesRead.reset();
+      readAndAssertBytesRead(inputStream, secondBytesToRead);
       inputStream.unbuffer();
-      bytesRead.assertDiffEquals(12);
+      LOG.info("stream statistics after second read {}", streamStatsStr);
+      bytesRead.assertDiffEquals(secondBytesToRead);
+      final long bytesInClose = bytesReadInClose.diff();
+      expectedFinalBytesRead = firstBytesToRead + secondBytesToRead;
+      expectedTotalBytesRead = expectedFinalBytesRead
+          + bytesInUnbuffer + bytesInClose;
+
+      totalBytesRead.assertDiffEquals(expectedTotalBytesRead);
     } finally {
+      LOG.info("Closing stream");
       IOUtils.closeStream(inputStream);
     }
+    LOG.info("stream statistics after close {}", streamStatsStr);
 
     // Validate that closing the file does not further change the statistics
-    bytesRead.assertDiffEquals(12);
+    totalBytesRead.assertDiffEquals(expectedTotalBytesRead);
 
     // Validate that the input stream stats are correct when the file is closed
-    assertEquals("S3AInputStream statistics were not updated properly", 12,
-            ((S3AInputStream) inputStream.getWrappedStream())
-                    .getS3AStreamStatistics().bytesRead);
+    S3AInputStreamStatistics streamStatistics = ((S3AInputStream) inputStream
+        .getWrappedStream())
+        .getS3AStreamStatistics();
+    Assertions.assertThat(streamStatistics)
+        .describedAs("Stream statistics %s", streamStatistics)
+        .hasFieldOrPropertyWithValue("bytesRead",
+            expectedFinalBytesRead)
+        .hasFieldOrPropertyWithValue("totalBytesRead", expectedTotalBytesRead);
+    assertEquals("S3AInputStream statistics were not updated properly in "
+        + streamStatsStr,
+        expectedFinalBytesRead,
+            streamStatistics.getBytesRead());
   }
 
   private boolean isObjectStreamOpen(FSDataInputStream inputStream) {

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/ITestS3GuardEmptyDirs.java

@@ -225,7 +225,7 @@ public class ITestS3GuardEmptyDirs extends AbstractS3ATestBase {
       // if DDB is the metastore, then we expect no FS requests to be made
       // at all.
       S3ATestUtils.MetricDiff listMetric = new S3ATestUtils.MetricDiff(fs,
-          Statistic.OBJECT_LIST_REQUESTS);
+          Statistic.OBJECT_LIST_REQUEST);
       S3ATestUtils.MetricDiff getMetric = new S3ATestUtils.MetricDiff(fs,
           Statistic.OBJECT_METADATA_REQUESTS);
       // do a getFile status with empty dir flag

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/MockS3AFileSystem.java

@@ -39,11 +39,14 @@ import org.apache.hadoop.fs.RemoteIterator;
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.fs.s3a.auth.delegation.EncryptionSecrets;
 import org.apache.hadoop.fs.s3a.commit.staging.StagingTestBase;
+import org.apache.hadoop.fs.s3a.statistics.CommitterStatistics;
+import org.apache.hadoop.fs.s3a.statistics.impl.EmptyS3AStatisticsContext;
 import org.apache.hadoop.fs.s3a.s3guard.BulkOperationState;
+import org.apache.hadoop.fs.statistics.DurationTrackerFactory;
 import org.apache.hadoop.util.Progressable;
 
+import static org.apache.hadoop.fs.statistics.IOStatisticsSupport.stubDurationTrackerFactory;
 import static org.apache.hadoop.thirdparty.com.google.common.base.Preconditions.checkNotNull;
-import static org.apache.hadoop.io.IOUtils.cleanupWithLogger;
 
 /**
  * Relays FS calls to the mocked FS, allows for some extra logging with
@@ -83,8 +86,6 @@ public class MockS3AFileSystem extends S3AFileSystem {
    * mock FS.
    */
   private int logEvents = LOG_NAME;
-  private final S3AInstrumentation instrumentation =
-      new S3AInstrumentation(FS_URI);
   private Configuration conf;
   private WriteOperationHelper writeHelper;
 
@@ -146,12 +147,12 @@ public class MockS3AFileSystem extends S3AFileSystem {
   public void initialize(URI name, Configuration originalConf)
       throws IOException {
     conf = originalConf;
-    writeHelper = new WriteOperationHelper(this, conf);
+    writeHelper = new WriteOperationHelper(this, conf,
+        new EmptyS3AStatisticsContext());
   }
 
   @Override
   public void close() {
-    cleanupWithLogger(LOG, instrumentation);
   }
 
   @Override
@@ -359,12 +360,17 @@ public class MockS3AFileSystem extends S3AFileSystem {
   }
 
   @Override
-  public S3AInstrumentation.CommitterStatistics newCommitterStatistics() {
-    return instrumentation.newCommitterStatistics();
+  public CommitterStatistics newCommitterStatistics() {
+    return EmptyS3AStatisticsContext.EMPTY_COMMITTER_STATISTICS;
   }
 
   @Override
   public void operationRetried(Exception ex) {
     /** no-op */
   }
+
+  @Override
+  protected DurationTrackerFactory getDurationTrackerFactory() {
+    return stubDurationTrackerFactory();
+  }
 }

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/MockS3ClientFactory.java

@@ -28,6 +28,8 @@ import com.amazonaws.services.s3.AmazonS3;
 import com.amazonaws.services.s3.model.MultipartUploadListing;
 import com.amazonaws.services.s3.model.Region;
 
+import org.apache.hadoop.fs.s3a.statistics.StatisticsFromAwsSdk;
+
 /**
  * An {@link S3ClientFactory} that returns Mockito mocks of the {@link AmazonS3}
  * interface suitable for unit testing.
@@ -38,7 +40,8 @@ public class MockS3ClientFactory implements S3ClientFactory {
   public AmazonS3 createS3Client(URI name,
       final String bucket,
       final AWSCredentialsProvider credentialSet,
-      final String userAgentSuffix) {
+      final String userAgentSuffix,
+      final StatisticsFromAwsSdk statisticsFromAwsSdks) {
     AmazonS3 s3 = mock(AmazonS3.class);
     when(s3.doesBucketExist(bucket)).thenReturn(true);
     when(s3.doesBucketExistV2(bucket)).thenReturn(true);

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/S3ATestUtils.java

@@ -40,6 +40,8 @@ import org.apache.hadoop.fs.s3a.impl.ContextAccessors;
 import org.apache.hadoop.fs.s3a.impl.StatusProbeEnum;
 import org.apache.hadoop.fs.s3a.impl.StoreContext;
 import org.apache.hadoop.fs.s3a.impl.StoreContextBuilder;
+import org.apache.hadoop.fs.s3a.statistics.BlockOutputStreamStatistics;
+import org.apache.hadoop.fs.s3a.statistics.impl.EmptyS3AStatisticsContext;
 import org.apache.hadoop.fs.s3a.s3guard.MetadataStore;
 import org.apache.hadoop.fs.s3a.s3guard.MetadataStoreCapabilities;
 import org.apache.hadoop.fs.s3a.s3guard.S3Guard;
@@ -54,6 +56,7 @@ import org.apache.hadoop.service.Service;
 import org.apache.hadoop.service.ServiceOperations;
 import org.apache.hadoop.util.BlockingThreadPoolExecutorService;
 import org.apache.hadoop.util.ReflectionUtils;
+import org.apache.hadoop.util.functional.CallableRaisingIOE;
 
 import com.amazonaws.auth.AWSCredentialsProvider;
 import org.hamcrest.core.Is;
@@ -836,9 +839,9 @@ public final class S3ATestUtils {
    * @param <T> type of operation.
    */
   public static <T> void callQuietly(final Logger log,
-      final Invoker.Operation<T> operation) {
+      final CallableRaisingIOE<T> operation) {
     try {
-      operation.execute();
+      operation.apply();
     } catch (Exception e) {
       log.info(e.toString(), e);
     }
@@ -933,7 +936,7 @@ public final class S3ATestUtils {
         .setExecutorCapacity(DEFAULT_EXECUTOR_CAPACITY)
         .setInvoker(
             new Invoker(RetryPolicies.TRY_ONCE_THEN_FAIL, Invoker.LOG_EVENT))
-        .setInstrumentation(new S3AInstrumentation(name))
+        .setInstrumentation(new EmptyS3AStatisticsContext())
         .setStorageStatistics(new S3AStorageStatistics())
         .setInputPolicy(S3AInputPolicy.Normal)
         .setChangeDetectionPolicy(
@@ -1230,7 +1233,7 @@ public final class S3ATestUtils {
    * @param out output stream
    * @return the (active) stats of the write
    */
-  public static S3AInstrumentation.OutputStreamStatistics
+  public static BlockOutputStreamStatistics
       getOutputStreamStatistics(FSDataOutputStream out) {
     S3ABlockOutputStream blockOutputStream
         = (S3ABlockOutputStream) out.getWrappedStream();

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/TestListing.java

@@ -18,9 +18,13 @@
 
 package org.apache.hadoop.fs.s3a;
 
-import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.RemoteIterator;
+import org.apache.hadoop.fs.statistics.IOStatistics;
+import org.apache.hadoop.fs.statistics.IOStatisticsSource;
+import org.apache.hadoop.fs.statistics.impl.IOStatisticsStore;
+
+import org.assertj.core.api.Assertions;
 import org.junit.Assert;
 import org.junit.Test;
 
@@ -31,8 +35,11 @@ import java.util.Iterator;
 import java.util.NoSuchElementException;
 import java.util.Set;
 
-import static org.apache.hadoop.fs.s3a.S3AUtils.ACCEPT_ALL;
-import static org.apache.hadoop.fs.s3a.Listing.ProvidedFileStatusIterator;
+import static org.apache.hadoop.fs.statistics.IOStatisticAssertions.extractStatistics;
+import static org.apache.hadoop.fs.statistics.IOStatisticAssertions.verifyStatisticCounterValue;
+import static org.apache.hadoop.fs.statistics.StoreStatisticNames.OBJECT_LIST_REQUEST;
+import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.iostatisticsStore;
+import static org.apache.hadoop.test.LambdaTestUtils.intercept;
 
 /**
  * Place for the S3A listing classes; keeps all the small classes under control.
@@ -40,11 +47,18 @@ import static org.apache.hadoop.fs.s3a.Listing.ProvidedFileStatusIterator;
 public class TestListing extends AbstractS3AMockTest {
 
   private static class MockRemoteIterator<S3AFileStatus> implements
-      RemoteIterator<S3AFileStatus> {
+      RemoteIterator<S3AFileStatus>, IOStatisticsSource {
+
+    private final IOStatisticsStore ioStatistics;
+
     private Iterator<S3AFileStatus> iterator;
 
     MockRemoteIterator(Collection<S3AFileStatus> source) {
       iterator = source.iterator();
+      this.ioStatistics = iostatisticsStore()
+          .withDurationTracking(OBJECT_LIST_REQUEST)
+          .build();
+      ioStatistics.incrementCounter(OBJECT_LIST_REQUEST);
     }
 
     public boolean hasNext() {
@@ -54,6 +68,11 @@ public class TestListing extends AbstractS3AMockTest {
     public S3AFileStatus next() {
       return iterator.next();
     }
+
+    @Override
+    public IOStatistics getIOStatistics() {
+      return ioStatistics;
+    }
   }
 
   private S3AFileStatus blankFileStatus(Path path) {
@@ -65,11 +84,9 @@ public class TestListing extends AbstractS3AMockTest {
     Path parent = new Path("/parent");
     Path liveChild = new Path(parent, "/liveChild");
     Path deletedChild = new Path(parent, "/deletedChild");
-    Path[] allFiles = {parent, liveChild, deletedChild};
-    Path[] liveFiles = {parent, liveChild};
 
     Listing listing = fs.getListing();
-    Collection<FileStatus> statuses = new ArrayList<>();
+    Collection<S3AFileStatus> statuses = new ArrayList<>();
     statuses.add(blankFileStatus(parent));
     statuses.add(blankFileStatus(liveChild));
     statuses.add(blankFileStatus(deletedChild));
@@ -92,7 +109,13 @@ public class TestListing extends AbstractS3AMockTest {
     while (reconcilingIterator.hasNext()) {
       actualPaths.add(reconcilingIterator.next().getPath());
     }
-    Assert.assertTrue(actualPaths.equals(expectedPaths));
+    Assertions.assertThat(actualPaths)
+        .describedAs("paths from iterator")
+        .isEqualTo(expectedPaths);
+
+    // now verify the stats went all the way through.
+    IOStatistics iostats = extractStatistics(reconcilingIterator);
+    verifyStatisticCounterValue(iostats, OBJECT_LIST_REQUEST, 1);
   }
 
   @Test
@@ -104,18 +127,13 @@ public class TestListing extends AbstractS3AMockTest {
     S3AFileStatus[] statuses = {
         s3aStatus
     };
-    ProvidedFileStatusIterator it = new ProvidedFileStatusIterator(statuses,
-        ACCEPT_ALL, new Listing.AcceptAllButS3nDirs());
+    RemoteIterator<S3AFileStatus> it = Listing.toProvidedFileStatusIterator(
+        statuses);
 
     Assert.assertTrue("hasNext() should return true first time", it.hasNext());
-    Assert.assertNotNull("first element should not be null", it.next());
+    Assert.assertEquals("first element from iterator",
+        s3aStatus, it.next());
     Assert.assertFalse("hasNext() should now be false", it.hasNext());
-    try {
-      it.next();
-      Assert.fail("next() should have thrown exception");
-    } catch (NoSuchElementException e) {
-      // Correct behavior.  Any other exceptions are propagated as failure.
-      return;
-    }
+    intercept(NoSuchElementException.class, it::next);
   }
 }

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/TestS3ABlockOutputStream.java

@@ -21,6 +21,7 @@ package org.apache.hadoop.fs.s3a;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.PathIOException;
 import org.apache.hadoop.fs.s3a.commit.PutTracker;
+import org.apache.hadoop.fs.s3a.statistics.impl.EmptyS3AStatisticsContext;
 import org.apache.hadoop.util.Progressable;
 import org.junit.Before;
 import org.junit.Test;
@@ -30,7 +31,6 @@ import java.io.IOException;
 import java.util.concurrent.ExecutorService;
 
 import static org.apache.hadoop.test.LambdaTestUtils.intercept;
-import static org.junit.Assert.*;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.spy;
@@ -50,11 +50,10 @@ public class TestS3ABlockOutputStream extends AbstractS3AMockTest {
     S3ADataBlocks.BlockFactory blockFactory =
         mock(S3ADataBlocks.BlockFactory.class);
     long blockSize = Constants.DEFAULT_MULTIPART_SIZE;
-    S3AInstrumentation.OutputStreamStatistics statistics = null;
     WriteOperationHelper oHelper = mock(WriteOperationHelper.class);
     PutTracker putTracker = mock(PutTracker.class);
     stream = spy(new S3ABlockOutputStream(fs, "", executorService,
-      progressable, blockSize, blockFactory, statistics, oHelper,
+      progressable, blockSize, blockFactory, null, oHelper,
       putTracker));
   }
 
@@ -70,7 +69,8 @@ public class TestS3ABlockOutputStream extends AbstractS3AMockTest {
     S3AFileSystem s3a = mock(S3AFileSystem.class);
     when(s3a.getBucket()).thenReturn("bucket");
     WriteOperationHelper woh = new WriteOperationHelper(s3a,
-        new Configuration());
+        new Configuration(),
+        new EmptyS3AStatisticsContext());
     ByteArrayInputStream inputStream = new ByteArrayInputStream(
         "a".getBytes());
     // first one works

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/TestStreamChangeTracker.java

@@ -18,8 +18,6 @@
 
 package org.apache.hadoop.fs.s3a;
 
-import java.util.concurrent.atomic.AtomicLong;
-
 import com.amazonaws.AmazonServiceException;
 import com.amazonaws.SdkBaseException;
 import com.amazonaws.services.s3.Headers;
@@ -36,6 +34,7 @@ import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.PathIOException;
 import org.apache.hadoop.fs.s3a.impl.ChangeDetectionPolicy;
 import org.apache.hadoop.fs.s3a.impl.ChangeTracker;
+import org.apache.hadoop.fs.s3a.statistics.impl.CountingChangeTracker;
 import org.apache.hadoop.test.HadoopTestBase;
 
 import static org.apache.hadoop.fs.s3a.impl.ChangeDetectionPolicy.CHANGE_DETECTED;
@@ -359,7 +358,7 @@ public class TestStreamChangeTracker extends HadoopTestBase {
       final ChangeTracker tracker,
       final int expectedCount) {
     assertEquals("counter in tracker " + tracker,
-        expectedCount, tracker.getVersionMismatches().get());
+        expectedCount, tracker.getVersionMismatches());
   }
 
   /**
@@ -386,7 +385,7 @@ public class TestStreamChangeTracker extends HadoopTestBase {
         source,
         requireVersion);
     ChangeTracker tracker = new ChangeTracker(URI, policy,
-        new AtomicLong(0), objectAttributes);
+        new CountingChangeTracker(), objectAttributes);
     if (objectAttributes.getVersionId() == null
         && objectAttributes.getETag() == null) {
       assertFalse("Tracker should not have applied constraints " + tracker,

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/auth/ITestAssumeRole.java

@@ -51,6 +51,7 @@ import org.apache.hadoop.fs.s3a.commit.CommitOperations;
 import org.apache.hadoop.fs.s3a.commit.files.PendingSet;
 import org.apache.hadoop.fs.s3a.commit.files.SinglePendingCommit;
 import org.apache.hadoop.fs.s3a.s3guard.S3GuardTool;
+import org.apache.hadoop.fs.s3a.statistics.CommitterStatistics;
 
 import static org.apache.hadoop.fs.contract.ContractTestUtils.touch;
 import static org.apache.hadoop.fs.s3a.Constants.*;
@@ -62,6 +63,7 @@ import static org.apache.hadoop.fs.s3a.auth.RolePolicies.*;
 import static org.apache.hadoop.fs.s3a.auth.RoleTestUtils.forbidden;
 import static org.apache.hadoop.fs.s3a.auth.RoleTestUtils.newAssumedRoleConfig;
 import static org.apache.hadoop.fs.s3a.s3guard.S3GuardToolTestHelper.exec;
+import static org.apache.hadoop.fs.statistics.IOStatisticsLogging.ioStatisticsSourceToString;
 import static org.apache.hadoop.io.IOUtils.cleanupWithLogger;
 import static org.apache.hadoop.test.GenericTestUtils.assertExceptionContains;
 import static org.apache.hadoop.test.LambdaTestUtils.*;
@@ -573,8 +575,11 @@ public class ITestAssumeRole extends AbstractS3ATestBase {
             .addResources(directory(writeableDir))
     );
     roleFS = (S3AFileSystem) writeableDir.getFileSystem(conf);
-    CommitOperations fullOperations = new CommitOperations(fs);
-    CommitOperations operations = new CommitOperations(roleFS);
+    CommitterStatistics committerStatistics = fs.newCommitterStatistics();
+    CommitOperations fullOperations = new CommitOperations(fs,
+        committerStatistics);
+    CommitOperations operations = new CommitOperations(roleFS,
+        committerStatistics);
 
     File localSrc = File.createTempFile("source", "");
     writeCSVData(localSrc);
@@ -608,7 +613,7 @@ public class ITestAssumeRole extends AbstractS3ATestBase {
               name + CommitConstants.PENDING_SUFFIX), true);
           assertTrue(src.delete());
         }));
-    progress.assertCount("Process counter is not expected",
+    progress.assertCount("progress counter is not expected",
         range);
 
     try {
@@ -652,6 +657,8 @@ public class ITestAssumeRole extends AbstractS3ATestBase {
     } finally {
       LOG.info("Cleanup");
       fullOperations.abortPendingUploadsUnderPath(readOnlyDir);
+      LOG.info("Committer statistics {}",
+          ioStatisticsSourceToString(committerStatistics));
     }
   }
 

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/auth/ITestRestrictedReadAccess.java

@@ -724,7 +724,7 @@ public class ITestRestrictedReadAccess extends AbstractS3ATestBase {
     S3ATestUtils.MetricDiff getMetric = new S3ATestUtils.MetricDiff(fs,
         Statistic.OBJECT_METADATA_REQUESTS);
     S3ATestUtils.MetricDiff listMetric = new S3ATestUtils.MetricDiff(fs,
-        Statistic.OBJECT_LIST_REQUESTS);
+        Statistic.OBJECT_LIST_REQUEST);
     FileStatus[] st;
     try {
       st = filter == null

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/auth/ProgressCounter.java

@@ -18,6 +18,8 @@
 
 package org.apache.hadoop.fs.s3a.auth;
 
+import java.util.concurrent.atomic.AtomicLong;
+
 import org.apache.hadoop.util.Progressable;
 
 import static org.junit.Assert.assertEquals;
@@ -27,14 +29,14 @@ import static org.junit.Assert.assertEquals;
  */
 public class ProgressCounter implements Progressable {
 
-  private long count;
+  private final AtomicLong count = new AtomicLong();
 
   public void progress() {
-    count++;
+    count.incrementAndGet();
   }
 
   public long getCount() {
-    return count;
+    return count.get();
   }
 
   public void assertCount(String message, int expected) {

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/auth/delegation/ITestSessionDelegationInFileystem.java

@@ -44,6 +44,8 @@ import org.apache.hadoop.fs.s3a.S3AEncryptionMethods;
 import org.apache.hadoop.fs.s3a.S3AFileSystem;
 import org.apache.hadoop.fs.s3a.S3ATestUtils;
 import org.apache.hadoop.fs.s3a.Statistic;
+import org.apache.hadoop.fs.s3a.statistics.StatisticsFromAwsSdk;
+import org.apache.hadoop.fs.s3a.statistics.impl.EmptyS3AStatisticsContext;
 import org.apache.hadoop.hdfs.tools.DelegationTokenFetcher;
 import org.apache.hadoop.io.Text;
 import org.apache.hadoop.mapreduce.security.TokenCache;
@@ -70,6 +72,7 @@ import static org.apache.hadoop.fs.s3a.auth.delegation.DelegationTokenIOExceptio
 import static org.apache.hadoop.fs.s3a.auth.delegation.MiniKerberizedHadoopCluster.ALICE;
 import static org.apache.hadoop.fs.s3a.auth.delegation.MiniKerberizedHadoopCluster.assertSecurityEnabled;
 import static org.apache.hadoop.fs.s3a.auth.delegation.S3ADelegationTokens.lookupS3ADelegationToken;
+import static org.apache.hadoop.fs.s3a.impl.InternalConstants.AWS_SDK_METRICS_ENABLED;
 import static org.apache.hadoop.test.LambdaTestUtils.doAs;
 import static org.apache.hadoop.test.LambdaTestUtils.intercept;
 import static org.hamcrest.Matchers.containsString;
@@ -211,7 +214,7 @@ public class ITestSessionDelegationInFileystem extends AbstractDelegationIT {
     S3ATestUtils.MetricDiff invocationDiff = new S3ATestUtils.MetricDiff(fs,
         Statistic.INVOCATION_GET_DELEGATION_TOKEN);
     S3ATestUtils.MetricDiff issueDiff = new S3ATestUtils.MetricDiff(fs,
-        Statistic.DELEGATION_TOKENS_ISSUED);
+        Statistic.DELEGATION_TOKEN_ISSUED);
     Token<AbstractS3ATokenIdentifier> token =
         requireNonNull(fs.getDelegationToken(""),
             "no token from filesystem " + fs);
@@ -305,6 +308,9 @@ public class ITestSessionDelegationInFileystem extends AbstractDelegationIT {
     describe("Delegation tokens can be passed to a new filesystem;"
         + " if role restricted, permissions are tightened.");
     S3AFileSystem fs = getFileSystem();
+    // force a probe of the remote FS to make sure its endpoint is valid
+    // (this always hits S3, even when S3Guard is enabled)
+    fs.getObjectMetadata(new Path("/"));
     readLandsatMetadata(fs);
 
     URI uri = fs.getUri();
@@ -365,7 +371,7 @@ public class ITestSessionDelegationInFileystem extends AbstractDelegationIT {
 
       S3ATestUtils.MetricDiff issueDiff = new S3ATestUtils.MetricDiff(
           delegatedFS,
-          Statistic.DELEGATION_TOKENS_ISSUED);
+          Statistic.DELEGATION_TOKEN_ISSUED);
 
       // verify that the FS returns the existing token when asked
       // so that chained deployments will work
@@ -561,8 +567,13 @@ public class ITestSessionDelegationInFileystem extends AbstractDelegationIT {
     conf.set(ENDPOINT, "");
     factory.setConf(conf);
     String host = landsat.getHost();
+    StatisticsFromAwsSdk awsStats = null;
+    if (AWS_SDK_METRICS_ENABLED) {
+      awsStats = new EmptyS3AStatisticsContext()
+          .newStatisticsFromAwsSdk();
+    }
     AmazonS3 s3 = factory.createS3Client(landsat, host, testing,
-        "ITestSessionDelegationInFileystem");
+        "ITestSessionDelegationInFileystem", awsStats);
 
     return Invoker.once("HEAD", host,
         () -> s3.getObjectMetadata(host, landsat.getPath().substring(1)));

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/commit/AbstractCommitITest.java

@@ -53,6 +53,7 @@ import static org.apache.hadoop.fs.s3a.Constants.*;
 import static org.apache.hadoop.fs.s3a.MultipartTestUtils.listMultipartUploads;
 import static org.apache.hadoop.fs.s3a.S3ATestUtils.*;
 import static org.apache.hadoop.fs.s3a.commit.CommitConstants.*;
+import static org.apache.hadoop.fs.statistics.IOStatisticsLogging.ioStatisticsToString;
 
 /**
  * Base test suite for committer operations.
@@ -460,6 +461,8 @@ public abstract class AbstractCommitITest extends AbstractS3ATestBase {
         commitDetails);
     LOG.info("Committer statistics: \n{}",
         successData.dumpMetrics("  ", " = ", "\n"));
+    LOG.info("Job IOStatistics: \n{}",
+        ioStatisticsToString(successData.getIOStatistics()));
     LOG.info("Diagnostics\n{}",
         successData.dumpDiagnostics("  ", " = ", "\n"));
     if (!committerName.isEmpty()) {
@@ -486,7 +489,7 @@ public abstract class AbstractCommitITest extends AbstractS3ATestBase {
    * @throws IOException failure to find/load the file
    * @throws AssertionError file is 0-bytes long,
    */
-  public static SuccessData loadSuccessFile(final S3AFileSystem fs,
+  public static SuccessData loadSuccessFile(final FileSystem fs,
       final Path outputPath, final String origin) throws IOException {
     ContractTestUtils.assertPathExists(fs,
         "Output directory " + outputPath
@@ -505,7 +508,9 @@ public abstract class AbstractCommitITest extends AbstractS3ATestBase {
             + success + " from " + origin
             + "; an S3A committer was not used",
         status.getLen() > 0);
-    LOG.info("Loading committer success file {}", success);
+    String body = ContractTestUtils.readUTF8(fs, success, -1);
+    LOG.info("Loading committer success file {}. Actual contents=\n{}", success,
+        body);
     return SuccessData.load(fs, success);
   }
 }

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/commit/AbstractITCommitProtocol.java

@@ -43,6 +43,7 @@ import org.apache.hadoop.fs.contract.ContractTestUtils;
 import org.apache.hadoop.fs.s3a.S3AFileSystem;
 import org.apache.hadoop.fs.s3a.commit.files.SuccessData;
 import org.apache.hadoop.fs.s3a.commit.magic.MagicS3GuardCommitter;
+import org.apache.hadoop.fs.statistics.IOStatisticsSnapshot;
 import org.apache.hadoop.io.IntWritable;
 import org.apache.hadoop.io.LongWritable;
 import org.apache.hadoop.io.MapFile;
@@ -77,6 +78,9 @@ import static org.apache.hadoop.fs.s3a.commit.InternalCommitterConstants.E_NO_SP
 import static org.apache.hadoop.fs.s3a.commit.InternalCommitterConstants.FS_S3A_COMMITTER_UUID;
 import static org.apache.hadoop.fs.s3a.commit.InternalCommitterConstants.FS_S3A_COMMITTER_UUID_SOURCE;
 import static org.apache.hadoop.fs.s3a.commit.InternalCommitterConstants.SPARK_WRITE_UUID;
+import static org.apache.hadoop.fs.s3a.Statistic.COMMITTER_TASKS_SUCCEEDED;
+import static org.apache.hadoop.fs.statistics.IOStatisticAssertions.assertThatStatisticCounter;
+import static org.apache.hadoop.fs.statistics.IOStatisticsLogging.ioStatisticsSourceToString;
 import static org.apache.hadoop.test.LambdaTestUtils.*;
 
 /**
@@ -1339,9 +1343,28 @@ public abstract class AbstractITCommitProtocol extends AbstractCommitITest {
     assertTrue("Committer does not have data to commit " + committer,
         committer.needsTaskCommit(tContext));
     commitTask(committer, tContext);
+    // at this point the committer tasks stats should be current.
+    IOStatisticsSnapshot snapshot = new IOStatisticsSnapshot(
+        committer.getIOStatistics());
+    String commitsCompleted = COMMITTER_TASKS_SUCCEEDED.getSymbol();
+    assertThatStatisticCounter(snapshot, commitsCompleted)
+        .describedAs("task commit count")
+        .isEqualTo(1L);
+
+
     commitJob(committer, jContext);
+    LOG.info("committer iostatistics {}",
+        ioStatisticsSourceToString(committer));
+
     // validate output
-    verifySuccessMarker(outDir, committer.getUUID());
+    SuccessData successData = verifySuccessMarker(outDir, committer.getUUID());
+
+    // the task commit count should get through the job commit
+    IOStatisticsSnapshot successStats = successData.getIOStatistics();
+    LOG.info("loaded statistics {}", successStats);
+    assertThatStatisticCounter(successStats, commitsCompleted)
+        .describedAs("task commit count")
+        .isEqualTo(1L);
   }
 
   /**

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/commit/integration/ITestS3ACommitterMRJob.java

@@ -80,7 +80,6 @@ import static org.apache.hadoop.fs.s3a.commit.CommitConstants._SUCCESS;
 import static org.apache.hadoop.fs.s3a.commit.InternalCommitterConstants.FS_S3A_COMMITTER_UUID;
 import static org.apache.hadoop.fs.s3a.commit.staging.Paths.getMultipartUploadCommitsDirectory;
 import static org.apache.hadoop.fs.s3a.commit.staging.StagingCommitterConstants.STAGING_UPLOADS;
-import static org.apache.hadoop.test.LambdaTestUtils.intercept;
 
 /**
  * Test an MR Job with all the different committers.

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/commit/staging/MockedStagingCommitter.java

@@ -28,6 +28,7 @@ import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.s3a.MockS3AFileSystem;
 import org.apache.hadoop.fs.s3a.commit.staging.StagingTestBase.ClientErrors;
 import org.apache.hadoop.fs.s3a.commit.staging.StagingTestBase.ClientResults;
+import org.apache.hadoop.fs.statistics.IOStatisticsSnapshot;
 import org.apache.hadoop.mapreduce.JobContext;
 import org.apache.hadoop.mapreduce.TaskAttemptContext;
 
@@ -76,7 +77,8 @@ class MockedStagingCommitter extends StagingCommitter {
 
   @Override
   protected void maybeCreateSuccessMarker(JobContext context,
-      List<String> filenames)
+      List<String> filenames,
+      final IOStatisticsSnapshot ioStatistics)
       throws IOException {
      //skipped
   }

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/impl/ITestPartialRenamesDeletes.java

@@ -58,8 +58,9 @@ import static org.apache.hadoop.fs.s3a.S3ATestUtils.MetricDiff;
 import static org.apache.hadoop.fs.s3a.S3ATestUtils.*;
 import static org.apache.hadoop.fs.s3a.S3AUtils.applyLocatedFiles;
 import static org.apache.hadoop.fs.s3a.Statistic.FILES_DELETE_REJECTED;
+import static org.apache.hadoop.fs.s3a.Statistic.OBJECT_BULK_DELETE_REQUEST;
 import static org.apache.hadoop.fs.s3a.Statistic.OBJECT_DELETE_OBJECTS;
-import static org.apache.hadoop.fs.s3a.Statistic.OBJECT_DELETE_REQUESTS;
+import static org.apache.hadoop.fs.s3a.Statistic.OBJECT_DELETE_REQUEST;
 import static org.apache.hadoop.fs.s3a.auth.RoleModel.Effects;
 import static org.apache.hadoop.fs.s3a.auth.RoleModel.Statement;
 import static org.apache.hadoop.fs.s3a.auth.RoleModel.directory;
@@ -666,7 +667,9 @@ public class ITestPartialRenamesDeletes extends AbstractS3ATestBase {
 
     // this set can be deleted by the role FS
     MetricDiff rejectionCount = new MetricDiff(roleFS, FILES_DELETE_REJECTED);
-    MetricDiff deleteVerbCount = new MetricDiff(roleFS, OBJECT_DELETE_REQUESTS);
+    MetricDiff deleteVerbCount = new MetricDiff(roleFS, OBJECT_DELETE_REQUEST);
+    MetricDiff bulkDeleteVerbCount = new MetricDiff(roleFS,
+        OBJECT_BULK_DELETE_REQUEST);
     MetricDiff deleteObjectCount = new MetricDiff(roleFS,
         OBJECT_DELETE_OBJECTS);
 
@@ -675,7 +678,9 @@ public class ITestPartialRenamesDeletes extends AbstractS3ATestBase {
     if (multiDelete) {
       // multi-delete status checks
       extractCause(MultiObjectDeleteException.class, ex);
-      deleteVerbCount.assertDiffEquals("Wrong delete request count", 1);
+      deleteVerbCount.assertDiffEquals("Wrong delete request count", 0);
+      bulkDeleteVerbCount.assertDiffEquals("Wrong bulk delete request count",
+          1);
       deleteObjectCount.assertDiffEquals("Number of keys in delete request",
           readOnlyFiles.size());
       rejectionCount.assertDiffEquals("Wrong rejection count",

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/impl/TestNetworkBinding.java

@@ -0,0 +1,105 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs.s3a.impl;
+
+import com.amazonaws.ClientConfiguration;
+import com.amazonaws.client.builder.AwsClientBuilder;
+import org.junit.Ignore;
+import org.junit.Test;
+
+import org.apache.hadoop.test.AbstractHadoopTestBase;
+
+import static org.apache.hadoop.fs.s3a.DefaultS3ClientFactory.createEndpointConfiguration;
+import static org.apache.hadoop.fs.s3a.impl.NetworkBinding.fixBucketRegion;
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Unit tests related to the {@link NetworkBinding} class.
+ */
+public class TestNetworkBinding extends AbstractHadoopTestBase {
+
+  private static final String US_EAST_1 = "us-east-1";
+
+  private static final String US_WEST_2 = "us-west-2";
+
+  @Test
+  public void testUSEast() {
+    assertRegionFixup(US_EAST_1, US_EAST_1);
+  }
+
+  @Test
+  public void testUSWest() {
+    assertRegionFixup(US_WEST_2, US_WEST_2);
+  }
+
+  @Test
+  public void testRegionUStoUSEast() {
+    assertRegionFixup("US", US_EAST_1);
+  }
+
+  @Test
+  public void testRegionNullToUSEast() {
+    assertRegionFixup(null, US_EAST_1);
+  }
+
+  private static void assertRegionFixup(String region, String expected) {
+    assertThat(fixBucketRegion(region))
+        .describedAs("Fixup of %s", region)
+        .isEqualTo(expected);
+  }
+
+  @Test
+  public void testNull() throws Throwable {
+    expectEndpoint("", true, "unused");
+  }
+
+  @Test
+  @Ignore("disabled until endpoint logic works for S3 client builder API")
+  public void testUSEastEndpoint() throws Throwable {
+    expectEndpoint(US_EAST_1, false, US_EAST_1);
+  }
+
+  @Test
+  @Ignore("disabled until endpoint logic works for S3 client builder API")
+  public void testUSWestEndpoint() throws Throwable {
+    expectEndpoint(US_WEST_2, false, US_WEST_2);
+  }
+
+  public void expectEndpoint(final String src,
+      final boolean expectNull,
+      final String expectRegion) {
+    AwsClientBuilder.EndpointConfiguration epr =
+        createEndpointConfiguration(src, new ClientConfiguration());
+    String eprStr = epr == null
+        ? "(empty)"
+        : ("(" + epr.getServiceEndpoint() + " " + epr.getSigningRegion());
+    if (expectNull) {
+      assertThat(epr)
+          .describedAs("Endpoint configuration of %s =",
+              src, eprStr)
+          .isNull();
+    } else {
+      assertThat(epr)
+          .describedAs("Endpoint configuration of %s =",
+              src, eprStr)
+          .hasFieldOrPropertyWithValue("serviceEndpoint", src)
+          .hasFieldOrPropertyWithValue("signingRegion", expectRegion);
+    }
+  }
+}

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/impl/TestNeworkBinding.java

@@ -1,61 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.apache.hadoop.fs.s3a.impl;
-
-import org.assertj.core.api.Assertions;
-import org.junit.Test;
-
-import org.apache.hadoop.test.HadoopTestBase;
-
-import static org.apache.hadoop.fs.s3a.impl.NetworkBinding.fixBucketRegion;
-
-/**
- * Unit tests related to the {@link NetworkBinding} class.
- */
-public class TestNeworkBinding extends HadoopTestBase {
-
-  private static final String US_EAST_1 = "us-east-1";
-  private static final String US_WEST_2 = "us-west-2";
-
-  @Test
-  public void testUSEast() {
-    assertRegionFixup(US_EAST_1, US_EAST_1);
-  }
-
-  @Test
-  public void testUSWest() {
-    assertRegionFixup(US_WEST_2, US_WEST_2);
-  }
-
-  @Test
-  public void testRegionUStoUSEast() {
-    assertRegionFixup("US", US_EAST_1);
-  }
-
-  @Test
-  public void testRegionNullToUSEast() {
-    assertRegionFixup(null, US_EAST_1);
-  }
-
-  private static void assertRegionFixup(String region, String expected) {
-    Assertions.assertThat(fixBucketRegion(region))
-        .describedAs("Fixup of %s", region)
-        .isEqualTo(expected);
-  }
-}

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/performance/AbstractS3ACostTest.java

@@ -20,6 +20,7 @@ package org.apache.hadoop.fs.s3a.performance;
 
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.util.EnumSet;
 import java.util.Set;
 import java.util.concurrent.Callable;
 
@@ -31,16 +32,19 @@ import org.apache.hadoop.fs.FSDataOutputStreamBuilder;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.contract.ContractTestUtils;
 import org.apache.hadoop.fs.s3a.AbstractS3ATestBase;
+import org.apache.hadoop.fs.s3a.Constants;
 import org.apache.hadoop.fs.s3a.S3AFileStatus;
 import org.apache.hadoop.fs.s3a.S3AFileSystem;
 import org.apache.hadoop.fs.s3a.Statistic;
 import org.apache.hadoop.fs.s3a.Tristate;
 import org.apache.hadoop.fs.s3a.impl.DirectoryPolicy;
 import org.apache.hadoop.fs.s3a.impl.StatusProbeEnum;
+import org.apache.hadoop.fs.s3a.statistics.StatisticTypeEnum;
 
 import static org.apache.hadoop.fs.s3a.Constants.*;
 import static org.apache.hadoop.fs.s3a.S3ATestUtils.*;
-import static org.apache.hadoop.fs.s3a.Statistic.*;
+import static org.apache.hadoop.fs.s3a.Statistic.OBJECT_BULK_DELETE_REQUEST;
+import static org.apache.hadoop.fs.s3a.Statistic.OBJECT_DELETE_REQUEST;
 import static org.apache.hadoop.fs.s3a.performance.OperationCost.*;
 import static org.apache.hadoop.fs.s3a.performance.OperationCostValidator.expect;
 import static org.apache.hadoop.fs.s3a.performance.OperationCostValidator.probe;
@@ -83,6 +87,18 @@ public class AbstractS3ACostTest extends AbstractS3ATestBase {
 
   private OperationCostValidator costValidator;
 
+  /**
+   * Is bulk deletion enabled?
+   */
+  private boolean isBulkDelete;
+
+  /**
+   * Which statistic measures marker deletion?
+   * this is the bulk delete statistic by default;
+   * if that is disabled it becomes the single delete counter.
+   */
+  private Statistic deleteMarkerStatistic;
+
   public AbstractS3ACostTest(
       final boolean s3guard,
       final boolean keepMarkers,
@@ -149,23 +165,24 @@ public class AbstractS3ACostTest extends AbstractS3ATestBase {
         .isEqualTo(isKeepingMarkers()
             ? DirectoryPolicy.MarkerPolicy.Keep
             : DirectoryPolicy.MarkerPolicy.Delete);
-
-    // insert new metrics so as to keep the list sorted
-    costValidator = OperationCostValidator.builder(getFileSystem())
-        .withMetrics(
-            DIRECTORIES_CREATED,
-            DIRECTORIES_DELETED,
-            FAKE_DIRECTORIES_DELETED,
-            FILES_DELETED,
-            INVOCATION_COPY_FROM_LOCAL_FILE,
-            OBJECT_COPY_REQUESTS,
-            OBJECT_DELETE_REQUESTS,
-            OBJECT_DELETE_OBJECTS,
-            OBJECT_LIST_REQUESTS,
-            OBJECT_METADATA_REQUESTS,
-            OBJECT_PUT_BYTES,
-            OBJECT_PUT_REQUESTS)
-        .build();
+    // All counter statistics of the filesystem are added as metrics.
+    // Durations too, as they have counters of success and failure.
+    OperationCostValidator.Builder builder = OperationCostValidator.builder(
+        getFileSystem());
+    EnumSet.allOf(Statistic.class).stream()
+        .filter(s ->
+            s.getType() == StatisticTypeEnum.TYPE_COUNTER
+                || s.getType() == StatisticTypeEnum.TYPE_DURATION)
+        .forEach(s -> builder.withMetric(s));
+    costValidator = builder.build();
+
+    // determine bulk delete settings
+    final Configuration fsConf = getFileSystem().getConf();
+    isBulkDelete = fsConf.getBoolean(Constants.ENABLE_MULTI_DELETE,
+        true);
+    deleteMarkerStatistic = isBulkDelete()
+        ? OBJECT_BULK_DELETE_REQUEST
+        : OBJECT_DELETE_REQUEST;
   }
 
   public void assumeUnguarded() {
@@ -369,8 +386,7 @@ public class AbstractS3ACostTest extends AbstractS3ATestBase {
    * Execute a closure expecting an exception.
    * @param clazz type of exception
    * @param text text to look for in exception (optional)
-   * @param head expected head request count.
-   * @param list expected list request count.
+   * @param cost expected cost declaration.
    * @param eval closure to evaluate
    * @param <T> return type of closure
    * @param <E> exception type
@@ -647,4 +663,20 @@ public class AbstractS3ACostTest extends AbstractS3ATestBase {
                     getFileSystem(), status.getPath())))
         .isEqualTo(expected);
   }
+
+  /**
+   * Is bulk deletion enabled?
+   */
+  protected boolean isBulkDelete() {
+    return isBulkDelete;
+  }
+
+  /**
+   * Which statistic measures marker deletion?
+   * this is the bulk delete statistic by default;
+   * if that is disabled it becomes the single delete counter.
+   */
+  protected Statistic getDeleteMarkerStatistic() {
+    return deleteMarkerStatistic;
+  }
 }

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/performance/ITestS3ADeleteCost.java

@@ -47,6 +47,10 @@ import static org.apache.hadoop.test.LambdaTestUtils.intercept;
  * Use metrics to assert about the cost of file API calls.
  * <p></p>
  * Parameterized on guarded vs raw. and directory marker keep vs delete.
+ * There's extra complexity related to bulk/non-bulk delete calls.
+ * If bulk deletes are disabled, many more requests are made to delete
+ * parent directories. The counters of objects deleted are constant
+ * irrespective of the delete mode.
  */
 @RunWith(Parameterized.class)
 public class ITestS3ADeleteCost extends AbstractS3ACostTest {
@@ -112,18 +116,19 @@ public class ITestS3ADeleteCost extends AbstractS3ACostTest {
         // if deleting markers, look for the parent too
         probe(rawAndDeleting, OBJECT_METADATA_REQUESTS,
             FILESTATUS_FILE_PROBE_H + FILESTATUS_DIR_PROBE_H),
-        withWhenRaw(OBJECT_LIST_REQUESTS,
+        withWhenRaw(OBJECT_LIST_REQUEST,
             FILESTATUS_FILE_PROBE_L + FILESTATUS_DIR_PROBE_L),
         with(DIRECTORIES_DELETED, 0),
         with(FILES_DELETED, 1),
 
         // keeping: create no parent dirs or delete parents
         withWhenKeeping(DIRECTORIES_CREATED, 0),
-        withWhenKeeping(OBJECT_DELETE_REQUESTS, DELETE_OBJECT_REQUEST),
+        withWhenKeeping(OBJECT_DELETE_OBJECTS, DELETE_OBJECT_REQUEST),
 
         // deleting: create a parent and delete any of its parents
         withWhenDeleting(DIRECTORIES_CREATED, 1),
-        withWhenDeleting(OBJECT_DELETE_REQUESTS,
+        // two objects will be deleted
+        withWhenDeleting(OBJECT_DELETE_OBJECTS,
             DELETE_OBJECT_REQUEST
                 + DELETE_MARKER_REQUEST)
     );
@@ -160,7 +165,7 @@ public class ITestS3ADeleteCost extends AbstractS3ACostTest {
         // if deleting markers, look for the parent too
         probe(rawAndDeleting, OBJECT_METADATA_REQUESTS,
             FILESTATUS_FILE_PROBE_H + FILESTATUS_DIR_PROBE_H),
-        withWhenRaw(OBJECT_LIST_REQUESTS,
+        withWhenRaw(OBJECT_LIST_REQUEST,
             FILESTATUS_FILE_PROBE_L + FILESTATUS_DIR_PROBE_L),
         with(DIRECTORIES_DELETED, 0),
         with(FILES_DELETED, 1),
@@ -169,10 +174,10 @@ public class ITestS3ADeleteCost extends AbstractS3ACostTest {
         with(DIRECTORIES_CREATED, 0),
 
         // keeping: create no parent dirs or delete parents
-        withWhenKeeping(OBJECT_DELETE_REQUESTS, DELETE_OBJECT_REQUEST),
+        withWhenKeeping(OBJECT_DELETE_REQUEST, DELETE_OBJECT_REQUEST),
 
         // deleting: create a parent and delete any of its parents
-        withWhenDeleting(OBJECT_DELETE_REQUESTS,
+        withWhenDeleting(OBJECT_DELETE_REQUEST,
             DELETE_OBJECT_REQUEST));
   }
 
@@ -199,22 +204,20 @@ public class ITestS3ADeleteCost extends AbstractS3ACostTest {
 
     LOG.info("creating sub directory {}", subDir);
     // one dir created, possibly a parent removed
+    final int fakeDirectoriesToDelete = directoriesInPath(subDir) - 1;
     verifyMetrics(() -> {
       mkdirs(subDir);
       return "after mkdir(subDir) " + getMetricSummary();
     },
         with(DIRECTORIES_CREATED, 1),
         with(DIRECTORIES_DELETED, 0),
-        withWhenKeeping(OBJECT_DELETE_REQUESTS, 0),
+        withWhenKeeping(getDeleteMarkerStatistic(), 0),
         withWhenKeeping(FAKE_DIRECTORIES_DELETED, 0),
-        withWhenDeleting(OBJECT_DELETE_REQUESTS, DELETE_MARKER_REQUEST),
+        withWhenDeleting(getDeleteMarkerStatistic(),
+            isBulkDelete() ? DELETE_MARKER_REQUEST : fakeDirectoriesToDelete),
         // delete all possible fake dirs above the subdirectory
         withWhenDeleting(FAKE_DIRECTORIES_DELETED,
-            directoriesInPath(subDir) - 1));
-
-    int dirDeleteRequests  = 1;
-    int fileDeleteRequests  = 0;
-    int totalDeleteRequests = dirDeleteRequests + fileDeleteRequests;
+            fakeDirectoriesToDelete));
 
     LOG.info("About to delete {}", parent);
     // now delete the deep tree.
@@ -223,8 +226,6 @@ public class ITestS3ADeleteCost extends AbstractS3ACostTest {
       return "deleting parent dir " + parent + " " + getMetricSummary();
     },
 
-        // two directory markers will be deleted in a single request
-        with(OBJECT_DELETE_REQUESTS, totalDeleteRequests),
         // keeping: the parent dir marker needs deletion alongside
         // the subdir one.
         withWhenKeeping(OBJECT_DELETE_OBJECTS, dirsCreated),
@@ -265,6 +266,7 @@ public class ITestS3ADeleteCost extends AbstractS3ACostTest {
     // creating a file should trigger demise of the src dir marker
     // unless markers are being kept
 
+    final int directories = directoriesInPath(srcDir);
     verifyMetrics(() -> {
       file(new Path(srcDir, "source.txt"));
       LOG.info("Metrics: {}\n{}", getMetricSummary(), getFileSystem());
@@ -273,12 +275,13 @@ public class ITestS3ADeleteCost extends AbstractS3ACostTest {
         with(DIRECTORIES_CREATED, 0),
         with(DIRECTORIES_DELETED, 0),
         // keeping: no delete operations.
-        withWhenKeeping(OBJECT_DELETE_REQUESTS, 0),
+        withWhenKeeping(getDeleteMarkerStatistic(), 0),
         withWhenKeeping(FAKE_DIRECTORIES_DELETED, 0),
         // delete all possible fake dirs above the file
-        withWhenDeleting(OBJECT_DELETE_REQUESTS, 1),
+        withWhenDeleting(getDeleteMarkerStatistic(),
+            isBulkDelete() ? 1: directories),
         withWhenDeleting(FAKE_DIRECTORIES_DELETED,
-            directoriesInPath(srcDir)));
+            directories));
   }
 
 }

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/performance/ITestS3ARenameCost.java

@@ -35,6 +35,7 @@ import org.apache.hadoop.fs.s3a.S3AFileSystem;
 
 import static org.apache.hadoop.fs.s3a.Statistic.*;
 import static org.apache.hadoop.fs.s3a.performance.OperationCost.*;
+import static org.apache.hadoop.fs.s3a.performance.OperationCostValidator.probe;
 
 /**
  * Use metrics to assert about the cost of file API calls.
@@ -97,19 +98,34 @@ public class ITestS3ARenameCost extends AbstractS3ACostTest {
     // rename the source file to the destination file.
     // this tests file rename, not dir rename
     // as srcFile2 exists, the parent dir of srcFilePath must not be created.
+    final int directoriesInPath = directoriesInPath(destDir);
     verifyMetrics(() ->
             execRename(srcFilePath, destFilePath),
         whenRaw(RENAME_SINGLE_FILE_DIFFERENT_DIR),
         with(DIRECTORIES_CREATED, 0),
         with(DIRECTORIES_DELETED, 0),
         // keeping: only the core delete operation is issued.
-        withWhenKeeping(OBJECT_DELETE_REQUESTS, DELETE_OBJECT_REQUEST),
+        withWhenKeeping(OBJECT_DELETE_REQUEST, DELETE_OBJECT_REQUEST),
         withWhenKeeping(FAKE_DIRECTORIES_DELETED, 0),
+        withWhenKeeping(OBJECT_DELETE_OBJECTS, 1),
+
         // deleting: delete any fake marker above the destination.
-        withWhenDeleting(OBJECT_DELETE_REQUESTS,
-            DELETE_OBJECT_REQUEST + DELETE_MARKER_REQUEST),
+        // the actual request count depends on whether bulk delete is
+        // enabled or not
+
+        // no bulk delete: multiple marker calls
+        probe(isDeleting() && !isBulkDelete(), OBJECT_DELETE_REQUEST,
+            DELETE_OBJECT_REQUEST + directoriesInPath),
+
+        // bulk delete: split up
+        probe(isDeleting() && isBulkDelete(), OBJECT_DELETE_REQUEST,
+                DELETE_OBJECT_REQUEST),
+        probe(isDeleting() && isBulkDelete(), OBJECT_BULK_DELETE_REQUEST,
+            DELETE_MARKER_REQUEST),
         withWhenDeleting(FAKE_DIRECTORIES_DELETED,
-            directoriesInPath(destDir)));
+            directoriesInPath),
+        withWhenDeleting(OBJECT_DELETE_OBJECTS,
+            directoriesInPath + 1));
 
     assertIsFile(destFilePath);
     assertIsDirectory(srcDir);
@@ -139,7 +155,7 @@ public class ITestS3ARenameCost extends AbstractS3ACostTest {
         whenRaw(RENAME_SINGLE_FILE_SAME_DIR),
         with(OBJECT_COPY_REQUESTS, 1),
         with(DIRECTORIES_CREATED, 0),
-        with(OBJECT_DELETE_REQUESTS, DELETE_OBJECT_REQUEST),
+        with(OBJECT_DELETE_REQUEST, DELETE_OBJECT_REQUEST),
         with(FAKE_DIRECTORIES_DELETED, 0));
   }
 
@@ -164,7 +180,7 @@ public class ITestS3ARenameCost extends AbstractS3ACostTest {
           // here we expect there to be no fake directories
           with(DIRECTORIES_CREATED, 0),
           // one for the renamed file only
-          with(OBJECT_DELETE_REQUESTS,
+          with(OBJECT_DELETE_REQUEST,
               DELETE_OBJECT_REQUEST),
           // no directories are deleted: This is root
           with(DIRECTORIES_DELETED, 0),
@@ -196,7 +212,7 @@ public class ITestS3ARenameCost extends AbstractS3ACostTest {
           with(DIRECTORIES_DELETED, 0),
           with(FAKE_DIRECTORIES_DELETED, 0),
           with(FILES_DELETED, 1),
-          with(OBJECT_DELETE_REQUESTS, DELETE_OBJECT_REQUEST),
+          with(OBJECT_DELETE_REQUEST, DELETE_OBJECT_REQUEST),
           whenRaw(FILE_STATUS_FILE_PROBE)); /* no need to look at parent. */
 
     } finally {

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/performance/OperationCost.java

@@ -51,6 +51,8 @@ public final class OperationCost {
 
   /**
    * Delete cost when deleting a marker.
+   * Note: if bulk delete is disabled, this changes to being
+   * the number of directories deleted.
    */
   public static final int DELETE_MARKER_REQUEST = DELETE_OBJECT_REQUEST;
 

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/performance/OperationCostValidator.java

@@ -31,11 +31,15 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import org.apache.hadoop.fs.s3a.S3AFileSystem;
+import org.apache.hadoop.fs.s3a.S3AInstrumentation;
 import org.apache.hadoop.fs.s3a.S3ATestUtils;
 import org.apache.hadoop.fs.s3a.Statistic;
+import org.apache.hadoop.fs.statistics.impl.IOStatisticsStore;
+import org.apache.hadoop.metrics2.lib.MutableCounter;
+import org.apache.hadoop.metrics2.lib.MutableMetric;
 
 import static java.util.Objects.requireNonNull;
-import static org.apache.hadoop.fs.s3a.Statistic.OBJECT_LIST_REQUESTS;
+import static org.apache.hadoop.fs.s3a.Statistic.OBJECT_LIST_REQUEST;
 import static org.apache.hadoop.fs.s3a.Statistic.OBJECT_METADATA_REQUESTS;
 import static org.apache.hadoop.test.LambdaTestUtils.intercept;
 
@@ -91,15 +95,30 @@ public final class OperationCostValidator {
   private final Map<String, S3ATestUtils.MetricDiff> metricDiffs
       = new TreeMap<>();
 
+  /**
+   * Instrumentation's IO Statistics.
+   */
+  private final IOStatisticsStore ioStatistics;
+
   /**
    * Build the instance.
    * @param builder builder containing all options.
    */
   private OperationCostValidator(Builder builder) {
-    builder.metrics.forEach(stat ->
-        metricDiffs.put(stat.getSymbol(),
-            new S3ATestUtils.MetricDiff(builder.filesystem, stat)));
+    S3AFileSystem fs = builder.filesystem;
+    S3AInstrumentation instrumentation = fs.getInstrumentation();
+    for (Statistic stat : builder.metrics) {
+      String symbol = stat.getSymbol();
+      MutableMetric metric = instrumentation.lookupMetric(symbol);
+      if (metric instanceof MutableCounter) {
+        // only counters are used in the cost tracking;
+        // other statistics are ignored.
+        metricDiffs.put(symbol,
+            new S3ATestUtils.MetricDiff(fs, stat));
+      }
+    }
     builder.metrics.clear();
+    ioStatistics = instrumentation.getIOStatistics();
   }
 
   /**
@@ -137,6 +156,7 @@ public final class OperationCostValidator {
       ExpectedProbe... expectedA) throws Exception {
     List<ExpectedProbe> expected = Arrays.asList(expectedA);
     resetMetricDiffs();
+
     // verify that 1+ probe is enabled
     assumeProbesEnabled(expected);
     // if we get here, then yes.
@@ -147,8 +167,9 @@ public final class OperationCostValidator {
         "operation returning "
             + (r != null ? r.toString() : "null");
     LOG.info("{}", text);
-    LOG.info("state {}", this);
+    LOG.info("state {}", this.toString());
     LOG.info("probes {}", expected);
+    LOG.info("IOStatistics {}", ioStatistics);
     for (ExpectedProbe ed : expected) {
       ed.verify(this, text);
     }
@@ -246,7 +267,8 @@ public final class OperationCostValidator {
      * @return this
      */
     public Builder withMetric(Statistic statistic) {
-      return withMetric(statistic);
+      metrics.add(statistic);
+      return this;
     }
 
     /**
@@ -330,7 +352,7 @@ public final class OperationCostValidator {
       boolean enabled, OperationCost cost) {
     return probes(enabled,
         probe(OBJECT_METADATA_REQUESTS, cost.head()),
-        probe(OBJECT_LIST_REQUESTS, cost.list()));
+        probe(OBJECT_LIST_REQUEST, cost.list()));
   }
 
   /**

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/s3guard/ITestDynamoDBMetadataStoreAuthoritativeMode.java

@@ -54,7 +54,7 @@ import static org.apache.hadoop.fs.s3a.Constants.S3_METADATA_STORE_IMPL;
 import static org.apache.hadoop.fs.s3a.S3ATestUtils.assume;
 import static org.apache.hadoop.fs.s3a.S3ATestUtils.removeBaseAndBucketOverrides;
 import static org.apache.hadoop.fs.s3a.S3AUtils.applyLocatedFiles;
-import static org.apache.hadoop.fs.s3a.Statistic.OBJECT_LIST_REQUESTS;
+import static org.apache.hadoop.fs.s3a.Statistic.OBJECT_LIST_REQUEST;
 import static org.apache.hadoop.fs.s3a.Statistic.S3GUARD_METADATASTORE_AUTHORITATIVE_DIRECTORIES_UPDATED;
 import static org.apache.hadoop.fs.s3a.Statistic.S3GUARD_METADATASTORE_RECORD_WRITES;
 import static org.apache.hadoop.fs.s3a.s3guard.AuthoritativeAuditOperation.ERROR_PATH_NOT_AUTH_IN_FS;
@@ -330,7 +330,7 @@ public class ITestDynamoDBMetadataStoreAuthoritativeMode
     touchFile(nestedFile2);
 
     S3ATestUtils.MetricDiff objListRequests =
-        new S3ATestUtils.MetricDiff(authFS, OBJECT_LIST_REQUESTS);
+        new S3ATestUtils.MetricDiff(authFS, OBJECT_LIST_REQUEST);
 
     RemoteIterator<LocatedFileStatus> statusIterator =
         authFS.listFiles(dir, true);
@@ -372,7 +372,7 @@ public class ITestDynamoDBMetadataStoreAuthoritativeMode
     touchFile(nestedFile2);
 
     S3ATestUtils.MetricDiff objListRequests =
-        new S3ATestUtils.MetricDiff(authFS, OBJECT_LIST_REQUESTS);
+        new S3ATestUtils.MetricDiff(authFS, OBJECT_LIST_REQUEST);
 
     RemoteIterator<LocatedFileStatus> statusIterator =
         authFS.listFiles(dir, true);
@@ -766,7 +766,7 @@ public class ITestDynamoDBMetadataStoreAuthoritativeMode
     S3ATestUtils.MetricDiff authDirsMarked = new S3ATestUtils.MetricDiff(authFS,
         S3GUARD_METADATASTORE_AUTHORITATIVE_DIRECTORIES_UPDATED);
     S3ATestUtils.MetricDiff listRequests = new S3ATestUtils.MetricDiff(authFS,
-        OBJECT_LIST_REQUESTS);
+        OBJECT_LIST_REQUEST);
     final T call = fn.call();
     authDirsMarked.assertDiffEquals(updates);
     listRequests.assertDiffEquals(lists);

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/s3guard/ITestDynamoDBMetadataStoreScale.java

@@ -21,6 +21,7 @@ package org.apache.hadoop.fs.s3a.s3guard;
 import javax.annotation.Nullable;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -49,7 +50,6 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.StorageStatistics;
 import org.apache.hadoop.fs.contract.ContractTestUtils;
-import org.apache.hadoop.fs.impl.WrappedIOException;
 import org.apache.hadoop.fs.s3a.AWSServiceThrottledException;
 import org.apache.hadoop.fs.s3a.Invoker;
 import org.apache.hadoop.fs.s3a.S3AFileStatus;
@@ -532,7 +532,7 @@ public class ITestDynamoDBMetadataStoreScale
         LOG.info("Deleting {}", p);
         list.add(p);
       });
-    } catch (WrappedIOException e) {
+    } catch (UncheckedIOException e) {
       // the iterator may have overloaded; swallow if so.
       if (!(e.getCause() instanceof AWSServiceThrottledException)) {
         throw e;

hadoop-tools/hadoop-aws/src/test/java/org/apache/hadoop/fs/s3a/scale/AbstractSTestS3AHugeFiles.java

@@ -25,8 +25,7 @@ import java.util.concurrent.atomic.AtomicLong;
 import com.amazonaws.event.ProgressEvent;
 import com.amazonaws.event.ProgressEventType;
 import com.amazonaws.event.ProgressListener;
-import org.apache.hadoop.fs.FileStatus;
-import org.apache.hadoop.fs.s3a.S3ATestUtils;
+import org.assertj.core.api.Assertions;
 import org.junit.FixMethodOrder;
 import org.junit.Test;
 import org.junit.runners.MethodSorters;
@@ -36,17 +35,24 @@ import org.slf4j.LoggerFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FSDataInputStream;
 import org.apache.hadoop.fs.FSDataOutputStream;
+import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.StorageStatistics;
 import org.apache.hadoop.fs.contract.ContractTestUtils;
 import org.apache.hadoop.fs.s3a.S3AFileSystem;
-import org.apache.hadoop.fs.s3a.S3AInstrumentation;
+import org.apache.hadoop.fs.s3a.S3ATestUtils;
 import org.apache.hadoop.fs.s3a.Statistic;
+import org.apache.hadoop.fs.s3a.statistics.BlockOutputStreamStatistics;
+import org.apache.hadoop.fs.statistics.IOStatistics;
 import org.apache.hadoop.util.Progressable;
 
 import static org.apache.hadoop.fs.contract.ContractTestUtils.*;
 import static org.apache.hadoop.fs.s3a.Constants.*;
 import static org.apache.hadoop.fs.s3a.S3ATestUtils.*;
+import static org.apache.hadoop.fs.statistics.IOStatisticsLogging.demandStringifyIOStatistics;
+import static org.apache.hadoop.fs.statistics.IOStatisticsLogging.ioStatisticsSourceToString;
+import static org.apache.hadoop.fs.statistics.IOStatisticsSupport.retrieveIOStatistics;
+import static org.apache.hadoop.fs.statistics.IOStatisticsSupport.snapshotIOStatistics;
 
 /**
  * Scale test which creates a huge file.
@@ -170,7 +176,7 @@ public abstract class AbstractSTestS3AHugeFiles extends S3AScaleTestBase {
     Statistic putBytesPending = Statistic.OBJECT_PUT_BYTES_PENDING;
 
     ContractTestUtils.NanoTimer timer = new ContractTestUtils.NanoTimer();
-    S3AInstrumentation.OutputStreamStatistics streamStatistics;
+    BlockOutputStreamStatistics streamStatistics;
     long blocksPer10MB = blocksPerMB * 10;
     ProgressCallback progress = new ProgressCallback(timer);
     try (FSDataOutputStream out = fs.create(fileToCreate,
@@ -221,8 +227,20 @@ public abstract class AbstractSTestS3AHugeFiles extends S3AScaleTestBase {
     logFSState();
     bandwidth(timer, filesize);
     LOG.info("Statistics after stream closed: {}", streamStatistics);
+    IOStatistics iostats = snapshotIOStatistics(
+        retrieveIOStatistics(getFileSystem()));
+    LOG.info("IOStatistics after upload: {}",
+        demandStringifyIOStatistics(iostats));
     long putRequestCount = storageStatistics.getLong(putRequests);
     Long putByteCount = storageStatistics.getLong(putBytes);
+    Assertions.assertThat(putRequestCount)
+        .describedAs("Put request count from filesystem stats %s",
+            iostats)
+        .isGreaterThan(0);
+    Assertions.assertThat(putByteCount)
+        .describedAs("putByteCount count from filesystem stats %s",
+            iostats)
+        .isGreaterThan(0);
     LOG.info("PUT {} bytes in {} operations; {} MB/operation",
         putByteCount, putRequestCount,
         putByteCount / (putRequestCount * _1MB));
@@ -234,7 +252,7 @@ public abstract class AbstractSTestS3AHugeFiles extends S3AScaleTestBase {
         "Put file " + fileToCreate + " of size " + filesize);
     if (streamStatistics != null) {
       assertEquals("actively allocated blocks in " + streamStatistics,
-          0, streamStatistics.blocksActivelyAllocated());
+          0, streamStatistics.getBlocksActivelyAllocated());
     }
   }
 
@@ -541,12 +559,7 @@ public abstract class AbstractSTestS3AHugeFiles extends S3AScaleTestBase {
    */
   @Test
   public void test_900_dumpStats() {
-    StringBuilder sb = new StringBuilder();
-
-    getFileSystem().getStorageStatistics()
-        .forEach(kv -> sb.append(kv.toString()).append("\n"));
-
-    LOG.info("Statistics\n{}", sb);
+    LOG.info("Statistics\n{}", ioStatisticsSourceToString(getFileSystem()));
   }
 
   protected void deleteHugeFile() throws IOException {