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  1. JDK
  2. JDK-8180175

ObjectSynchronizer only needs to iterate in-use monitors

    Details

    • Type: Enhancement
    • Status: Resolved
    • Priority: P3
    • Resolution: Fixed
    • Affects Version/s: 9, 10
    • Fix Version/s: 10
    • Component/s: hotspot
    • Labels:
    • Subcomponent:
    • Resolved In Build:
      b21
    • CPU:
      generic
    • OS:
      generic

      Description

      ObjectSynchronizer::oops_do() currently iterates all monitor blocks, even free ones. With -XX:+MonitorInUseLists, each thread has its own in-use monitors list, and ObjectSynchronizer has a global gOmInUseList for moribund threads. Iterating over in-use monitors only significantly inmproves scanning time for monitors, because it avoids scanning free blocks, improves caching (no padding, and better chances to have thread-local oops in cache already).

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              • Assignee:
                rkennke Roman Kennke
                Reporter:
                rkennke Roman Kennke
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                • Created:
                  Updated:
                  Resolved: