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  1. Hadoop Map/Reduce
  2. MAPREDUCE-1342

Potential JT deadlock in faulty TT tracking

    Details

    • Type: Bug
    • Status: Closed
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 0.20.1
    • Fix Version/s: 0.21.0
    • Component/s: jobtracker
    • Labels:
      None
    • Hadoop Flags:
      Reviewed
    • Release Note:
      Fix for a potential deadlock in the global blacklist of tasktrackers feature.

      Description

      JT$FaultyTrackersInfo.incrementFaults first locks potentiallyFaultyTrackers, and then calls blackListTracker, which calls removeHostCapacity, which locks JT.taskTrackers
      On the other hand, JT.blacklistedTaskTrackers() locks taskTrackers, then calls faultyTrackers.isBlacklisted() which goes on to lock potentiallyFaultyTrackers.

      I haven't produced such a deadlock, but the lock ordering here is inverted and therefore could deadlock.

      Not sure if this goes back to 0.21 or just in trunk.

        Attachments

        1. cycle0.png
          35 kB
          Todd Lipcon
        2. mapreduce-1342-1.patch
          8 kB
          Sreekanth Ramakrishnan
        3. mapreduce-1342-2.patch
          2 kB
          Sreekanth Ramakrishnan
        4. patch-1342.txt
          2 kB
          Amareshwari Sriramadasu
        5. patch-1342-0.21.txt
          8 kB
          Amareshwari Sriramadasu
        6. patch-1342-1.txt
          2 kB
          Amareshwari Sriramadasu
        7. patch-1342-2.txt
          7 kB
          Amareshwari Sriramadasu
        8. patch-1342-2-ydist.txt
          9 kB
          Amareshwari Sriramadasu
        9. patch-1342-3.txt
          8 kB
          Amareshwari Sriramadasu
        10. patch-1342-3-ydist.txt
          9 kB
          Amareshwari Sriramadasu
        11. patch-1342-ydist.txt
          2 kB
          Amareshwari Sriramadasu

          Activity

            People

            • Assignee:
              amareshwari Amareshwari Sriramadasu
              Reporter:
              tlipcon Todd Lipcon
            • Votes:
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              Watchers:
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              Dates

              • Created:
                Updated:
                Resolved: