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  1. Hadoop Common
  2. HADOOP-922

Optimize small reads and seeks

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    Details

    • Type: Bug
    • Status: Closed
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 0.10.1
    • Fix Version/s: 0.11.0
    • Component/s: None
    • Labels:
      None

      Description

      A seek on a DFSInputStream causes causes the next read to re-open the socket connection to the datanode and fetch the remainder of the block all over again. This is not optimal.

      A small read followed by a small positive seek could re-utilize the data already fetched from the datanode as part of the previous read.

        Attachments

        1. smallreadseek4.patch
          3 kB
          Dhruba Borthakur

          Issue Links

          is related to

          New Feature - A new feature of the product, which has yet to be developed. HADOOP-519 HDFS File API should be extended to include positional read

          • Major - Major loss of function.
          • Closed

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              People

              • Assignee:
                dhruba Dhruba Borthakur
                Reporter:
                dhruba Dhruba Borthakur
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                Dates

                • Created:
                  Updated:
                  Resolved: