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  1. JDK
  2. JDK-8247593

Shenandoah: should not block pacing reporters

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    • gc
    • b02

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      Description

        After JDK-8247367, we are acquiring the _wait_monitor in ShenandoahPacer::report_internal. That runs into potential deadlocks with threads that are waiting on the same lock *and* safepointing at the same time, against the concurrent workers that want to report the progress before returning for subsequent safepoint.

        Also, this introduces latency/scalability hogs on fastpaths in concurrent mark.

        We are better off deferring the actual notification to a separate (periodic) task.

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            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8250938 Shenandoah: should not block pacing reporters

            • P2 - Crashes, loss of data, severe memory leak.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8251070 Shenandoah: should not block pacing reporters

            • P2 - Crashes, loss of data, severe memory leak.
            • Resolved
            relates to

            Enhancement - null JDK-8247367 Shenandoah: pacer should wait on lock instead of exponential backoff

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

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                shade Aleksey Shipilev
                shade Aleksey Shipilev
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                  Created:
                  Updated:
                  Resolved: