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  1. Hadoop HDFS
  2. HDFS-4697

short-circuit reads do not honor readahead settings

    Details

    • Type: Bug
    • Status: Closed
    • Priority: Minor
    • Resolution: Duplicate
    • Affects Version/s: 2.0.3-alpha
    • Fix Version/s: 2.3.0
    • Component/s: hdfs-client
    • Labels:
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      Description

      Neither the new nor the legacy short-circuit read implementations honor dfs.datanode.readahead.bytes. This can result in scenarios where non-short-circuit reads are faster for long reads, simply because they are doing more readahead, and SCR is not. We should do readahead in both cases if it is configured.

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              • Assignee:
                cmccabe Colin P. McCabe
                Reporter:
                cmccabe Colin P. McCabe
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                • Created:
                  Updated:
                  Resolved: