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  1. Sqoop
  2. SQOOP-603

Support small intervals in IntegerSplitter implementation

    Details

    • Type: Improvement
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 1.4.2
    • Fix Version/s: 1.4.3
    • Component/s: None
    • Labels:
      None

      Description

      IntegerSplitter is currently creating splits of following nature:

      minimal value <= x < splitPoint1
      splitPoint1 <= x < splitPoint2
      ...
      splitPointN <= x <= maximal value
      

      Please notice that upper bound is always with using condition "<" with exception of the last split that is using condition "<=". This is perfectly fine when creating reasonable amount of splits on very huge interval.

      This approach will however cause issues on very small intervals. For example following splits will be created on interval [0, 5] with 5 splits:

      • 0 <= x < 1
      • 1 <= x < 2
      • 2 <= x < 3
      • 3 <= x < 4
      • 4 <= x <= 5

      Notice that all splits have equal count of numbers except the last one having two numbers - 4 and 5. This becomes very huge issue when for example user needs to create one split per one partition as one mapper will end up with moving two partitions and thus entire job will take twice as long as the other ones.

      Jarcec

        Attachments

        1. SQOOP-603.patch
          3 kB
          Jarek Jarcec Cecho

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              • Assignee:
                jarcec Jarek Jarcec Cecho
                Reporter:
                jarcec Jarek Jarcec Cecho
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                • Created:
                  Updated:
                  Resolved: