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  1. Hadoop Common
  2. HADOOP-15292

Distcp's use of pread is slowing it down.

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    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Minor
    • Resolution: Fixed
    • Affects Version/s: 2.5.0
    • Fix Version/s: 3.1.0
    • Component/s: tools/distcp
    • Labels:
      None
    • Target Version/s:

      Description

      Distcp currently uses positioned-reads (in RetriableFileCopyCommand#copyBytes) when the source offset is > 0. This results in unnecessary overheads (new BlockReader being created on the client-side, multiple readBlock() calls to the Datanodes, each of which requires the creation of a BlockSender and an inputstream to the ReplicaInfo).

        Attachments

        1. HADOOP-15292.000.patch
          4 kB
          Virajith Jalaparti
        2. HADOOP-15292.001.patch
          8 kB
          Virajith Jalaparti
        3. HADOOP-15292.002.patch
          8 kB
          Virajith Jalaparti

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              • Assignee:
                virajith Virajith Jalaparti
                Reporter:
                virajith Virajith Jalaparti
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                Dates

                • Created:
                  Updated:
                  Resolved: