HDFS-5371. Merge change r1540197 from trunk.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1540200 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/io/retry/LossyRetryInvocationHandler.java

@@ -18,9 +18,9 @@
 package org.apache.hadoop.io.retry;
 
 import java.lang.reflect.Method;
-import java.net.UnknownHostException;
 
 import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.ipc.RetriableException;
 
 /**
  * A dummy invocation handler extending RetryInvocationHandler. It drops the
@@ -52,7 +52,7 @@ public class LossyRetryInvocationHandler<T> extends RetryInvocationHandler<T> {
     if (retryCount < this.numToDrop) {
       RetryCount.set(++retryCount);
       LOG.info("Drop the response. Current retryCount == " + retryCount);
-      throw new UnknownHostException("Fake Exception");
+      throw new RetriableException("Fake Exception");
     } else {
       LOG.info("retryCount == " + retryCount
           + ". It's time to normally process the response");

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/io/retry/RetryPolicies.java

@@ -558,27 +558,25 @@ public class RetryPolicies {
           isWrappedStandbyException(e)) {
         return new RetryAction(RetryAction.RetryDecision.FAILOVER_AND_RETRY,
             getFailoverOrRetrySleepTime(failovers));
-      } else if (e instanceof SocketException ||
-                 (e instanceof IOException && !(e instanceof RemoteException))) {
+      } else if (e instanceof RetriableException
+          || getWrappedRetriableException(e) != null) {
+        // RetriableException or RetriableException wrapped 
+        return new RetryAction(RetryAction.RetryDecision.RETRY,
+              getFailoverOrRetrySleepTime(retries));
+      } else if (e instanceof SocketException
+          || (e instanceof IOException && !(e instanceof RemoteException))) {
         if (isIdempotentOrAtMostOnce) {
           return RetryAction.FAILOVER_AND_RETRY;
         } else {
           return new RetryAction(RetryAction.RetryDecision.FAIL, 0,
-              "the invoked method is not idempotent, and unable to determine " +
-              "whether it was invoked");
+              "the invoked method is not idempotent, and unable to determine "
+                  + "whether it was invoked");
         }
       } else {
-        RetriableException re = getWrappedRetriableException(e);
-        if (re != null) {
-          return new RetryAction(RetryAction.RetryDecision.RETRY,
-              getFailoverOrRetrySleepTime(retries));
-        } else {
           return fallbackPolicy.shouldRetry(e, retries, failovers,
               isIdempotentOrAtMostOnce);
-        }
       }
     }
-    
   }
 
   /**

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -96,6 +96,9 @@ Release 2.3.0 - UNRELEASED
     HDFS-5436. Move HsFtpFileSystem and HFtpFileSystem into org.apache.hdfs.web
     (Haohui Mai via Arpit Agarwal)
 
+    HDFS-5371. Let client retry the same NN when 
+    "dfs.client.test.drop.namenode.response.number" is enabled. (jing9)
+
   OPTIMIZATIONS
 
     HDFS-5239.  Allow FSNamesystem lock fairness to be configurable (daryn)