MAPREDUCE-3678. The Map tasks logs should have the value of input split it processed. Contributed by Harsh J. (harsh)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1@1396035 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -84,6 +84,9 @@ Release 1.2.0 - unreleased
     MAPREDUCE-4556. FairScheduler: PoolSchedulable#updateDemand() has potential 
     redundant computation (kkambatl via tucu)
 
+    MAPREDUCE-3678. The Map tasks logs should have the value of input
+    split it processed. (harsh)
+
   OPTIMIZATIONS
 
     HDFS-2533. Backport: Remove needless synchronization on some FSDataSet

src/mapred/org/apache/hadoop/mapred/MapTask.java

@@ -454,6 +454,7 @@ class MapTask extends Task {
       job.setLong("map.input.start", fileSplit.getStart());
       job.setLong("map.input.length", fileSplit.getLength());
     }
+    LOG.info("Processing split: " + inputSplit);
   }
 
   static class NewTrackingRecordReader<K,V> 
@@ -727,6 +728,7 @@ class MapTask extends Task {
     org.apache.hadoop.mapreduce.InputSplit split = null;
     split = getSplitDetails(new Path(splitIndex.getSplitLocation()),
         splitIndex.getStartOffset());
+    LOG.info("Processing split: " + split);
 
     org.apache.hadoop.mapreduce.RecordReader<INKEY,INVALUE> input =
       new NewTrackingRecordReader<INKEY,INVALUE>