Map Reduce with sharded output can apply reduce on duplicate documents if a migration happened

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    • Type: Bug
    • Resolution: Done
    • Priority: Major - P3
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    • Affects Version/s: None
    • Component/s: MapReduce, Sharding
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    • ALL
    • Sharding 2018-02-12
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    • 3
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      Buildbot failure:

      http://buildbot.mongodb.org/builders/Linux%2032-bit/builds/5402

      If a migration happened on the map reduce job output collection right before the mapreduce.shardedfinish is called, there is a possibility that one of the shard still thinks he owns the chunk, whereas it has already donated it to another shard.

        1. mrShardedOutput_with_cmdResult.txt
          698 kB
        2. mrShardedOutput.js
          3.70 MB

              Assignee:
              Randolph Tan
              Reporter:
              Ian Whalen (Inactive)
              Votes:
              4 Vote for this issue
              Watchers:
              11 Start watching this issue

                Created:
                Updated:
                Resolved: