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  1. Pig
  2. PIG-2152

Null pointer exception while reporting progress

    Details

    • Type: Bug
    • Status: Closed
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 0.9.0
    • Fix Version/s: 0.9.1, 0.10.0
    • Component/s: None
    • Labels:
      None

      Description

      We have observed the following issues with code built from Pig 0.9 branch. We have not seen this with earlier versions; however, since this happens once in a while and is not reproducible at will it is not clear whether the issue is specific to 0.9 or not.

      Here is the stack:

      java.lang.NullPointerException at
      org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.ProgressableReporter.progress(ProgressableReporter.java:37)
      at
      org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POForEach.processPlan(POForEach.java:399)
      at
      org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POForEach.getNext(POForEach.java:284)
      at org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator.processInput(PhysicalOperator.java:290)
      at
      org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POLocalRearrange.getNext(POLocalRearrange.java:256)
      at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigMapBase.runPipeline(PigMapBase.java:261) at
      org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigMapBase.map(PigMapBase.java:256) at
      org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigMapBase.map(PigMapBase.java:58) at
      org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144) at
      org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:764) at
      org.apache.hadoop.mapred.MapTask.run(MapTask.java:370) at org.apache.hadoop.mapred.Child$4.run(Child.java:261) at
      java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:396) at
      org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1059) at
      org.apache.hadoop.mapred.Child.main(Child.java:255)

      Note that the code in progress function looks as follows:

      public void progress()

      { if(rep!=null) rep.progress(); }

      This points to some sort of synchronization issue

        Attachments

        1. PIG-2152.1.patch
          0.6 kB
          Thejas M Nair
        2. null_pointer_traces (copy)
          256 kB
          Vivek Padmanabhan

          Activity

            People

            • Assignee:
              thejas Thejas M Nair
              Reporter:
              olgan Olga Natkovich
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              Dates

              • Created:
                Updated:
                Resolved: