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  1. JDK
  2. JDK-8240511

Shenandoah: parallel safepoint workers count should be ParallelGCThreads

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    • Subcomponent:
      gc
    • Resolved In Build:
      b13

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        Description

        It is currently statically driven by:

          experimental(uint, ShenandoahParallelSafepointThreads, 4, \
                  "Number of parallel threads used for safepoint prolog/epilog") \

        This is troublesome either way:
         *) For small machines or containers where ergonomics figures out ParallelGCThreads=1, this trashes safepoint cleanup with excessive threads;
         *) For large machines where ergonomics figures out ParallelGCThreads >> 4, this holds back parallelism needed at cleanup.

        Should be just driven by ParallelGCThreads. ZGC drives this with ParallelGCThreads. G1 implicitly does the same.

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                Assignee:
                shade Aleksey Shipilev
                Reporter:
                shade Aleksey Shipilev
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                  Updated:
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