HADOOP-10657. Merge r1602941 from trunk.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1602942 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -82,6 +82,9 @@ Release 2.5.0 - UNRELEASED
 
     HADOOP-10688. Expose thread-level FileSystem StatisticsData (Sandy Ryza)
 
+    HADOOP-10657. Have RetryInvocationHandler log failover attempt at INFO
+    level. (Ming Ma via jing9)
+
   OPTIMIZATIONS
 
   BUG FIXES 

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

@@ -137,9 +137,7 @@ public class RetryInvocationHandler<T> implements RpcInvocationHandler {
               msg += " after " + invocationFailoverCount + " fail over attempts"; 
             }
             msg += ". Trying to fail over " + formatSleepMessage(action.delayMillis);
-            if (LOG.isDebugEnabled()) {
-              LOG.debug(msg, e);
-            }
+            LOG.info(msg, e);
           } else {
             if(LOG.isDebugEnabled()) {
               LOG.debug("Exception while invoking " + method.getName()