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  1. Hadoop Map/Reduce
  2. MAPREDUCE-5268

Improve history server startup performance

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Details

    • Improvement
    • Status: Closed
    • Major
    • Resolution: Fixed
    • 0.23.7, 2.0.4-alpha
    • 2.1.0-beta, 0.23.9
    • jobhistoryserver
    • None
    • Reviewed

    Description

      The history server can easily take many minutes to startup when there are a significant number of jobs to scan in the done directory. However the scanning of files is not the bottleneck, rather it's the heavy use of ConcurrentSkipListMap.size in HistoryFileManager.

      ConcurrentSkipListMap.size is a very expensive operation, especially on maps with many entries, as it has to scan every entry to compute the size. We should avoid calling this method or at least minimize its use.

      Attachments

        1. mr-5268.patch
          10 kB
          Karthik Kambatla
        2. mr-5268.patch
          11 kB
          Karthik Kambatla
        3. mr-5268.patch
          11 kB
          Karthik Kambatla
        4. mr-5268.patch
          10 kB
          Karthik Kambatla
        5. mr-5268.patch
          9 kB
          Karthik Kambatla
        6. mr-5268-prelim.patch
          5 kB
          Karthik Kambatla

        Activity

          People

            kasha Karthik Kambatla
            jlowe Jason Darrell Lowe
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            Dates

              Created:
              Updated:
              Resolved: