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  1. Hadoop HDFS
  2. HDFS-5182

BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid

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    Details

    • Type: Improvement
    • Status: Closed
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 3.0.0-alpha1
    • Fix Version/s: 2.6.0
    • Component/s: hdfs-client
    • Labels:
      None
    • Target Version/s:

      Description

      BlockReaderLocal must allow zero-copy reads only when the DN believes it's valid. This implies adding a new field to the response to REQUEST_SHORT_CIRCUIT_FDS. We also need some kind of heartbeat from the client to the DN, so that the DN can inform the client when the mapped region is no longer locked into memory.

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          is blocked by

          Sub-task - The sub-task of the issue HDFS-5634 allow BlockReaderLocal to switch between checksumming and not

          • Major - Major loss of function.
          • Closed
          relates to

          Sub-task - The sub-task of the issue HDFS-5521 skip checksums when reading a cached block via non-local reads

          • Major - Major loss of function.
          • Resolved

          Sub-task - The sub-task of the issue HDFS-5394 fix race conditions in DN caching and uncaching

          • Major - Major loss of function.
          • Closed
          There are no Sub-Tasks for this issue.

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              • Assignee:
                cmccabe Colin McCabe
                Reporter:
                cmccabe Colin McCabe
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                Dates

                • Created:
                  Updated:
                  Resolved: