Hadoop Common
  1. Hadoop Common
  2. HADOOP-5079

HashFunction inadvertently destroys some randomness

    Details

    • Type: Bug Bug
    • Status: Closed
    • Priority: Major Major
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 0.20.0
    • Component/s: util
    • Labels:
      None
    • Hadoop Flags:
      Reviewed

      Description

      HashFunction.hash restricts initval for the next hash to the [0, maxValue) range of the hash indexes returned. This is suboptimal, particularly for larger nbHash and smaller maxValue. Rather we should first set initval, then restrict the range for the result assignment.

      1. hadoop-core-hash-2.patch
        0.6 kB
        Jonathan Ellis
      2. hadoop-core-hash.patch
        0.6 kB
        Jonathan Ellis

        Activity

        Jonathan Ellis created issue -
        Jonathan Ellis made changes -
        Field Original Value New Value
        Attachment hadoop-core-hash.patch [ 12398264 ]
        Jonathan Ellis made changes -
        Status Open [ 1 ] Patch Available [ 10002 ]
        stack made changes -
        Hadoop Flags [Reviewed]
        Fix Version/s 0.20.0 [ 12313438 ]
        stack made changes -
        Status Patch Available [ 10002 ] In Progress [ 3 ]
        stack made changes -
        Assignee stack [ stack ]
        stack made changes -
        Status In Progress [ 3 ] Patch Available [ 10002 ]
        stack made changes -
        Resolution Fixed [ 1 ]
        Status Patch Available [ 10002 ] Resolved [ 5 ]
        Jonathan Ellis made changes -
        Attachment hadoop-core-hash-2.patch [ 12399055 ]
        Jonathan Ellis made changes -
        Status Resolved [ 5 ] Reopened [ 4 ]
        Resolution Fixed [ 1 ]
        Jonathan Ellis made changes -
        Hadoop Flags [Reviewed]
        Status Reopened [ 4 ] Patch Available [ 10002 ]
        Chris Douglas made changes -
        Hadoop Flags [Reviewed]
        Resolution Fixed [ 1 ]
        Status Patch Available [ 10002 ] Resolved [ 5 ]
        Chris Douglas made changes -
        Assignee stack [ stack ] Jonathan Ellis [ jbellis ]
        Jonathan Ellis made changes -
        Assignee Jonathan Ellis [ jbellis ] Chris Douglas [ chris.douglas ]
        Chris Douglas made changes -
        Assignee Chris Douglas [ chris.douglas ] Jonathan Ellis [ jbellis ]
        Nigel Daley made changes -
        Status Resolved [ 5 ] Closed [ 6 ]

          People

          • Assignee:
            Jonathan Ellis
            Reporter:
            Jonathan Ellis
          • Votes:
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            Watchers:
            2 Start watching this issue

            Dates

            • Created:
              Updated:
              Resolved:

              Development