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

["Jason Lowe (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/MAPREDUCE-5271?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13666300#comment-13666300 ] 

Jason Lowe commented on MAPREDUCE-5271:
---------------------------------------

This looks to be the same issue reported in MAPREDUCE-5034 and MAPREDUCE-4965.  The problem has since been fixed by having {{CompressAwarePath}} extend {{Path}}.
                
> Error: org.apache.hadoop.mapreduce.task.reduce.Shuffle$ShuffleError: error in shuffle in InMemoryMerger - Thread to merge in-memory shuffled map-outputs
> --------------------------------------------------------------------------------------------------------------------------------------------------------
>
>                 Key: MAPREDUCE-5271
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-5271
>             Project: Hadoop Map/Reduce
>          Issue Type: Bug
>          Components: jobtracker
>    Affects Versions: 2.0.0-alpha
>         Environment: linux 64
>            Reporter: lijuanhzou
>            Assignee: lijuanhzou
>              Labels: hadoop
>
>  (hadoop-2.0.0-cdh4.2.0)I encounter following question when do a simple words-count working.small input data is ok,there is problem when using big datas:
> Error: org.apache.hadoop.mapreduce.task.reduce.Shuffle$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)

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira