HDFS-12751. Ozone: SCM: update container allocated size to container db for all the open containers in ContainerStateManager#close. Contributed by Chen Liang.

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/scm/container/common/helpers/ContainerInfo.java

@@ -100,6 +100,10 @@ public class ContainerInfo
     return allocatedBytes;
   }
 
+  public void setAllocatedBytes(long allocatedBytes) {
+    this.allocatedBytes = allocatedBytes;
+  }
+
   public long getUsedBytes() {
     return usedBytes;
   }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/scm/container/ContainerMapping.java

@@ -16,6 +16,7 @@
  */
 package org.apache.hadoop.ozone.scm.container;
 
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hdfs.DFSUtil;
@@ -428,8 +429,58 @@ public class ContainerMapping implements Mapping {
     if (containerLeaseManager != null) {
       containerLeaseManager.shutdown();
     }
+    if (containerStateManager != null) {
+      flushContainerInfo();
+      containerStateManager.close();
+    }
     if (containerStore != null) {
       containerStore.close();
     }
   }
+
+  /**
+   * Since allocatedBytes of a container is only in memory, stored in
+   * containerStateManager, when closing ContainerMapping, we need to update
+   * this in the container store.
+   *
+   * @throws IOException
+   */
+  @VisibleForTesting
+  public void flushContainerInfo() throws IOException {
+    List<ContainerInfo> containers = containerStateManager.getAllContainers();
+    List<String> failedContainers = new ArrayList<>();
+    for (ContainerInfo info : containers) {
+      // even if some container updated failed, others can still proceed
+      try {
+        byte[] dbKey = info.getContainerName().getBytes(encoding);
+        byte[] containerBytes = containerStore.get(dbKey);
+        // TODO : looks like when a container is deleted, the container is
+        // removed from containerStore but not containerStateManager, so it can
+        // return info of a deleted container. may revisit this in the future,
+        // for now, just skip a not-found container
+        if (containerBytes != null) {
+          OzoneProtos.SCMContainerInfo oldInfoProto =
+              OzoneProtos.SCMContainerInfo.PARSER.parseFrom(containerBytes);
+          ContainerInfo oldInfo = ContainerInfo.fromProtobuf(oldInfoProto);
+          oldInfo.setAllocatedBytes(info.getAllocatedBytes());
+          containerStore.put(dbKey, oldInfo.getProtobuf().toByteArray());
+        } else {
+          LOG.debug("Container state manager has container {} but not found " +
+              "in container store, a deleted container?",
+              info.getContainerName());
+        }
+      } catch (IOException ioe) {
+        failedContainers.add(info.getContainerName());
+      }
+    }
+    if (!failedContainers.isEmpty()) {
+      throw new IOException("Error in flushing container info from container " +
+          "state manager: " + failedContainers);
+    }
+  }
+
+  @VisibleForTesting
+  public MetadataStore getContainerStore() {
+    return containerStore;
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/scm/container/ContainerStateManager.java

@@ -38,6 +38,7 @@ import org.slf4j.LoggerFactory;
 
 import java.io.Closeable;
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
@@ -222,6 +223,17 @@ public class ContainerStateManager implements Closeable {
     }
   }
 
+  /**
+   * Return the info of all the containers kept by the in-memory mapping.
+   *
+   * @return the list of all container info.
+   */
+  List<ContainerInfo> getAllContainers() {
+    List<ContainerInfo> list = new ArrayList<>();
+    containers.forEach((key, value) -> list.addAll(value));
+    return list;
+  }
+
   // 1. Client -> SCM: Begin_create
   // 2. Client -> Datanode: create
   // 3. Client -> SCM: complete    {SCM:Creating ->OK}

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/ozone/scm/container/TestContainerStateManager.java

@@ -33,6 +33,7 @@ import org.junit.Test;
 import org.junit.rules.ExpectedException;
 
 import java.io.IOException;
+import java.util.Random;
 
 /**
  * Tests for ContainerStateManager.
@@ -245,6 +246,43 @@ public class TestContainerStateManager {
         xceiverClientManager.getType(), xceiverClientManager.getFactor(),
         OzoneProtos.LifeCycleState.CLOSED).size();
     Assert.assertEquals(1, containers);
+  }
 
+  @Test
+  public void testUpdatingAllocatedBytes() throws Exception {
+    String container1 = "container" + RandomStringUtils.randomNumeric(5);
+    scm.allocateContainer(xceiverClientManager.getType(),
+        xceiverClientManager.getFactor(), container1);
+    scmContainerMapping.updateContainerState(container1,
+        OzoneProtos.LifeCycleEvent.BEGIN_CREATE);
+    scmContainerMapping.updateContainerState(container1,
+        OzoneProtos.LifeCycleEvent.COMPLETE_CREATE);
+
+    Random ran = new Random();
+    long allocatedSize = 0;
+    for (int i = 0; i<5; i++) {
+      long size = Math.abs(ran.nextLong() % OzoneConsts.GB);
+      allocatedSize += size;
+      // trigger allocating bytes by calling getMatchingContainer
+      ContainerInfo info = stateManager
+          .getMatchingContainer(size, OzoneProtos.Owner.OZONE,
+              xceiverClientManager.getType(), xceiverClientManager.getFactor(),
+              OzoneProtos.LifeCycleState.OPEN);
+      Assert.assertEquals(container1, info.getContainerName());
+
+      ContainerMapping containerMapping =
+          (ContainerMapping)scmContainerMapping;
+      // manually trigger a flush, this will persist the allocated bytes value
+      // to disk
+      containerMapping.flushContainerInfo();
+
+      // the persisted value should always be equal to allocated size.
+      byte[] containerBytes =
+          containerMapping.getContainerStore().get(container1.getBytes());
+      OzoneProtos.SCMContainerInfo infoProto =
+          OzoneProtos.SCMContainerInfo.PARSER.parseFrom(containerBytes);
+      ContainerInfo currentInfo = ContainerInfo.fromProtobuf(infoProto);
+      Assert.assertEquals(allocatedSize, currentInfo.getAllocatedBytes());
+    }
   }
 }