Hadoop HDFS
  1. Hadoop HDFS
  2. HDFS-4697

short-circuit reads do not honor readahead settings

    Details

    • Type: Bug Bug
    • Status: Closed
    • Priority: Minor Minor
    • Resolution: Duplicate
    • Affects Version/s: 2.0.3-alpha
    • Fix Version/s: 2.3.0
    • Component/s: hdfs-client
    • Labels:
      None

      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.

        Issue Links

          Activity

          Colin Patrick McCabe created issue -
          Colin Patrick McCabe made changes -
          Field Original Value New Value
          Assignee Colin Patrick McCabe [ cmccabe ]
          Affects Version/s 2.0.3-alpha [ 12323274 ]
          Component/s hdfs-client [ 12312928 ]
          Todd Lipcon made changes -
          Link This issue duplicates HDFS-3228 [ HDFS-3228 ]
          Colin Patrick McCabe made changes -
          Status Open [ 1 ] Resolved [ 5 ]
          Fix Version/s 2.3.0 [ 12325255 ]
          Resolution Fixed [ 1 ]
          Colin Patrick McCabe made changes -
          Resolution Fixed [ 1 ]
          Status Resolved [ 5 ] Reopened [ 4 ]
          Colin Patrick McCabe made changes -
          Status Reopened [ 4 ] Resolved [ 5 ]
          Resolution Duplicate [ 3 ]
          Colin Patrick McCabe made changes -
          Link This issue duplicates HDFS-5634 [ HDFS-5634 ]
          Vinod Kumar Vavilapalli made changes -
          Status Resolved [ 5 ] Closed [ 6 ]

            People

            • Assignee:
              Colin Patrick McCabe
              Reporter:
              Colin Patrick McCabe
            • Votes:
              0 Vote for this issue
              Watchers:
              15 Start watching this issue

              Dates

              • Created:
                Updated:
                Resolved:

                Development