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  1. Hadoop Common
  2. HADOOP-922

Optimize small reads and seeks

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Details

    • Bug
    • Status: Closed
    • Major
    • Resolution: Fixed
    • 0.10.1
    • 0.11.0
    • None
    • 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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            dhruba Dhruba Borthakur
            dhruba Dhruba Borthakur
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              Updated:
              Resolved:

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