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  1. Hadoop HDFS
  2. HDFS-4960

Unnecessary .meta seeks even when skip checksum is true

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Details

    • Bug
    • Status: Patch Available
    • Major
    • Resolution: Unresolved
    • 2.1.0-beta, 3.0.0-alpha1
    • None
    • None

    Description

      While attempting to benchmark an HBase + Hadoop 2.0 setup on SSDs, we found unnecessary seeks into .meta files, each seek was a 7 byte read at the head of the file - this attempts to validate the version #. Since the client is requesting no-checksum, we should not be needing to touch the .meta file at all.

      Since the purpose of skip checksum is to also avoid the performance penalty of the extra seek, we should not be seeking into .meta if skip checksum is true

      Attachments

        1. 4960-branch2.patch
          2 kB
          Varun Sharma
        2. 4960-trunk.patch
          2 kB
          Varun Sharma

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            varunsharma Varun Sharma
            varunsharma Varun Sharma

            Dates

              Created:
              Updated:

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