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  1. Hadoop HDFS
  2. HDFS-2834

ByteBuffer-based read API for DFSInputStream

    Details

    • Type: Improvement
    • Status: Closed
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 2.0.2-alpha
    • Component/s: hdfs-client, performance
    • Labels:
      None
    • Hadoop Flags:
      Reviewed

      Description

      The DFSInputStream read-path always copies bytes into a JVM-allocated byte[]. Although for many clients this is desired behaviour, in certain situations, such as native-reads through libhdfs, this imposes an extra copy penalty since the byte[] needs to be copied out again into a natively readable memory area.

      For these cases, it would be preferable to allow the client to supply its own buffer, wrapped in a ByteBuffer, to avoid that final copy overhead.

        Attachments

        1. HDFS-2834-no-common.patch
          60 kB
          Henry Robinson
        2. hdfs-2834-libhdfs-benchmark.png
          43 kB
          Henry Robinson
        3. HDFS-2834.patch
          66 kB
          Henry Robinson
        4. HDFS-2834.patch
          64 kB
          Henry Robinson
        5. HDFS-2834.9.patch
          49 kB
          Henry Robinson
        6. HDFS-2834.8.patch
          61 kB
          Henry Robinson
        7. HDFS-2834.7.patch
          61 kB
          Henry Robinson
        8. HDFS-2834.6.patch
          59 kB
          Henry Robinson
        9. HDFS-2834.5.patch
          59 kB
          Henry Robinson
        10. HDFS-2834.4.patch
          58 kB
          Henry Robinson
        11. HDFS-2834.3.patch
          63 kB
          Henry Robinson
        12. HDFS-2834.11.patch
          60 kB
          Henry Robinson
        13. HDFS-2834.10.patch
          48 kB
          Henry Robinson

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              • Assignee:
                henryr Henry Robinson
                Reporter:
                henryr Henry Robinson
              • Votes:
                1 Vote for this issue
                Watchers:
                32 Start watching this issue

                Dates

                • Created:
                  Updated:
                  Resolved: