Derby
  1. Derby
  2. DERBY-1704

Allow more concurrency in the lock manager

    Details

    • Type: Improvement Improvement
    • Status: Closed
    • Priority: Minor Minor
    • Resolution: Fixed
    • Affects Version/s: 10.2.1.6
    • Fix Version/s: 10.3.1.4
    • Component/s: Services
    • Labels:
      None
    • Urgency:
      Normal
    • Bug behavior facts:
      Performance

      Description

      I have seen indications of severe monitor contention in SinglePool
      (the current lock manager) when multiple threads access a Derby
      database concurrently. When a thread wants to lock an object, it needs
      to obtain the monitor for both SinglePool and LockSet (both of them
      are global synchronization points). This leads to poor scalability.

      We should investigate how to allow more concurrency in the lock
      manager, and either extend SinglePool or implement a new manager.

      1. cleanup6.diff
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      2. cleanup5.stat
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      3. cleanup5.diff
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      5. cleanup3.stat
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      6. cleanup3.diff
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      7. cleanup2.diff
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      8. cleanup1.v2.diff
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      10. cleanup1.diff
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      11. split-hashtables.diff
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      12. split-hashtables.stat
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      13. 1cpu.png
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      14. 2cpu.png
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      15. 8cpu.png
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        Activity

          People

          • Assignee:
            Knut Anders Hatlen
            Reporter:
            Knut Anders Hatlen
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            Dates

            • Created:
              Updated:
              Resolved:

              Development