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  1. Hadoop Map/Reduce
  2. MAPREDUCE-26

The shuffle keeps the ReduceTask locked while doing a FileSystem.rename leading to task timeouts

    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Major
    • Resolution: Not A Problem
    • Affects Version/s: None
    • Fix Version/s: None
    • Component/s: None
    • Labels:
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      Description

      The shuffle in ReduceTask.ReduceCopier.MapOutputCopier.copyOutput locks the entire ReduceTask while doing a FileSystem.rename operation. Unfortunately the RawLocalFileSystem implements rename as a copy and delete, which can take a long time. As a result the reduce is being killed as not reporting progress for 10 minutes.

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            • Assignee:
              owen.omalley Owen O'Malley
              Reporter:
              owen.omalley Owen O'Malley
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              • Created:
                Updated:
                Resolved: