svn merge -c 1379617 from trunk FIXES: MAPREDUCE-4604. In mapred-default, mapreduce.map.maxattempts & mapreduce.reduce.maxattempts defaults are set to 4 as well as mapreduce.job.maxtaskfailures.per.tracker. (Ravi Prakash via jeagles)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.1.0-alpha@1379621 13f79535-47bb-0310-9956-ffa450edef68

hadoop-mapreduce-project/CHANGES.txt

@@ -599,6 +599,10 @@ Release 0.23.3 - UNRELEASED
     MAPREDUCE-4600. TestTokenCache.java from MRV1 no longer compiles  (daryn 
     via bobby)
 
+    MAPREDUCE-4604. In mapred-default, mapreduce.map.maxattempts &
+    mapreduce.reduce.maxattempts defaults are set to 4 as well as
+    mapreduce.job.maxtaskfailures.per.tracker. (Ravi Prakash via jeagles)
+
 Release 0.23.2 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/JobConf.java

@@ -1357,7 +1357,7 @@ public class JobConf extends Configuration {
    * @return the maximum no. of failures of a given job per tasktracker.
    */
   public int getMaxTaskFailuresPerTracker() {
-    return getInt(JobContext.MAX_TASK_FAILURES_PER_TRACKER, 4); 
+    return getInt(JobContext.MAX_TASK_FAILURES_PER_TRACKER, 3);
   }
 
   /**

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/resources/mapred-default.xml

@@ -782,9 +782,12 @@
 
 <property>
   <name>mapreduce.job.maxtaskfailures.per.tracker</name>
-  <value>4</value>
+  <value>3</value>
   <description>The number of task-failures on a tasktracker of a given job 
-               after which new tasks of that job aren't assigned to it.
+               after which new tasks of that job aren't assigned to it. It
+               MUST be less than mapreduce.map.maxattempts and
+               mapreduce.reduce.maxattempts otherwise the failed task will
+               never be tried on a different node.
   </description>
 </property>
 

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-jobclient/src/test/java/org/apache/hadoop/conf/TestJobConf.java

@@ -21,6 +21,7 @@ import org.junit.Assert;
 import org.junit.Test;
 
 import org.apache.hadoop.mapred.JobConf;
+import org.apache.hadoop.mapred.JobContext;
 import org.apache.hadoop.mapreduce.MRJobConfig;
 
 public class TestJobConf {
@@ -185,4 +186,19 @@ public class TestJobConf {
     
     
   }
+
+  /**
+   * Ensure that by default JobContext.MAX_TASK_FAILURES_PER_TRACKER is less
+   * JobContext.MAP_MAX_ATTEMPTS and JobContext.REDUCE_MAX_ATTEMPTS so that
+   * failed tasks will be retried on other nodes
+   */
+  @Test
+  public void testMaxTaskFailuresPerTracker() {
+    JobConf jobConf = new JobConf(true);
+    Assert.assertTrue("By default JobContext.MAX_TASK_FAILURES_PER_TRACKER was "
+      + "not less than JobContext.MAP_MAX_ATTEMPTS and REDUCE_MAX_ATTEMPTS"
+      ,jobConf.getMaxTaskFailuresPerTracker() < jobConf.getMaxMapAttempts() &&
+      jobConf.getMaxTaskFailuresPerTracker() < jobConf.getMaxReduceAttempts()
+      );
+  }
 }

hadoop-mapreduce-project/src/java/mapred-default.xml

@@ -701,7 +701,7 @@
 
 <property>
   <name>mapreduce.job.maxtaskfailures.per.tracker</name>
-  <value>4</value>
+  <value>3</value>
   <description>The number of task-failures on a tasktracker of a given job 
                after which new tasks of that job aren't assigned to it.
   </description>