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  1. Hadoop Common
  2. HADOOP-15292

Distcp's use of pread is slowing it down.

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Details

    • Bug
    • Status: Resolved
    • Minor
    • Resolution: Fixed
    • 2.5.0
    • 3.1.0
    • tools/distcp
    • None

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

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              virajith Virajith Jalaparti
              virajith Virajith Jalaparti
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                Created:
                Updated:
                Resolved: