MAPREDUCE-3383. Duplicate job.getOutputValueGroupingComparator() in ReduceTask. Contributed by Binglin Chang

(cherry picked from commit c39012f4a0444f9e4b7d67957d5192127d143d90)

hadoop-mapreduce-project/CHANGES.txt

@@ -139,6 +139,9 @@ Release 2.8.0 - UNRELEASED
 
     MAPREDUCE-6342. Make POM project names consistent. (Rohith via devaraj)
 
+    MAPREDUCE-3383. Duplicate job.getOutputValueGroupingComparator() in
+    ReduceTask (Binglin Chang via jlowe)
+
 Release 2.7.1 - UNRELEASED
 
   INCOMPATIBLE CHANGES

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

@@ -436,7 +436,7 @@ public class ReduceTask extends Task {
               comparator, keyClass, valueClass, 
               job, reporter, umbilical) :
           new ReduceValuesIterator<INKEY,INVALUE>(rIter, 
-          job.getOutputValueGroupingComparator(), keyClass, valueClass, 
+          comparator, keyClass, valueClass,
           job, reporter);
       values.informReduceProgress();
       while (values.more()) {