[MAPREDUCE-5271] Error: org.apache.hadoop.mapreduce.task.reduce.Shuffle$ShuffleError: error in shuffle in InMemoryMerger - Thread to merge in-memory shuffled map-outputs

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.0.0-alpha
• Component/s: jobtracker
• Labels: hadoop

Environment

linux 64

• Assignee: lijuanhzou
• Reporter: lijuanhzou
• Created: 24/May/13 06:56
• Updated: 24/May/13 13:30

Description

(hadoop-2.0.0-cdh4.2.0)I encounter following question when do a simple words-count working.small input data is ok,there is problem when using big datas:
Error: org.apache.hadoop.mapreduce.task.reduce.Shuffle$ShuffleError: error in shuffle in InMemoryMerger - Thread to merge in-memory shuffled map-outputs
at org.apache.hadoop.mapreduce.task.reduce.Shuffle.run(Shuffle.java:121)
at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:379)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:157)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1408)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:152)
Caused by: java.lang.ClassCastException: org.apache.hadoop.mapreduce.task.reduce.MergeManagerImpl$CompressAwarePath cannot be cast to java.lang.Comparable
at java.util.TreeMap.put(TreeMap.java:542)
at java.util.TreeSet.add(TreeSet.java:238)
at org.apache.hadoop.mapreduce.task.reduce.MergeManagerImpl.closeOnDiskFile(MergeManagerImpl.java:340)
at org.apache.hadoop.mapreduce.task.reduce.MergeManagerImpl$InMemoryMerger.merge(MergeManagerImpl.java:495)
at org.apache.hadoop.mapreduce.task.reduce.MergeThread.run(MergeThread.java:94)