8316929: Shenandoah: Shenandoah degenerated GC and full GC need to cleanup old OopMapCache entries

[zhengyu123]

During STW root scan, interpreted frame's oop map may be cached. But due to limited cache size (32 entries per instance class), entries may be evicted to old entries list due to collision, should be cleanup in VM_Operation's doit_epilogue(), or risk leaking memory.

Test:
hotspot_gc_shenandoah (fastdebug and release on MacOSX)

---

Progress

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Issue

• JDK-8316929: Shenandoah: Shenandoah degenerated GC and full GC need to cleanup old OopMapCache entries (Bug - P3)

Reviewers

• Aleksey Shipilev (@shipilev - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back zgu! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@zhengyu123 The following labels will be automatically applied to this pull request:

• hotspot-gc
• shenandoah

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing lists. If you would like to change these labels, use the /label pull request command.

[mlbridge]

Webrevs

• 03: Full - Incremental (4f41dc14)
• 02: Full - Incremental (c1e9cf27)
• 01: Full - Incremental (b84d2cad)
• 00: Full (92dc4f4e)

[earthling-amzn]

This looks good to me. Does the issue also affect 17?

[zhengyu123]

This looks good to me. Does the issue also affect 17?

Yes. I updated affected versions in bug.

[zhengyu123]

@earthling-amzn @rkennke @shipilev Could you please (formal) review? Thanks!

[shipilev]

This looks okay, but I think you can "just" add OMC::cleanup_old_entries in VM_ShenandoahReferenceOperation destructor, without introducing the intermediary?

[zhengyu123]

This looks okay, but I think you can "just" add OMC::cleanup_old_entries in VM_ShenandoahReferenceOperation destructor, without introducing the intermediary?

This looks okay, but I think you can "just" add OMC::cleanup_old_entries in VM_ShenandoahReferenceOperation destructor, without introducing the intermediary?

Place the call in doit_epilogue() for the symmetry with other GCs. But you are right, we don't need another VM operation.

[shipilev]

Looks fine, thanks!

[openjdk]

@zhengyu123 This change now passes all automated pre-integration checks.

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After integration, the commit message for the final commit will be:

8316929: Shenandoah: Shenandoah degenerated GC and full GC need to cleanup old OopMapCache entries

Reviewed-by: shade

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At the time when this comment was updated there had been 1 new commit pushed to the master branch:

• 878d27d: 8317273: compiler/codecache/OverflowCodeCacheTest.java fails transiently on Graal

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[zhengyu123]

Thanks, @shipilev

[zhengyu123]

/integrate

[openjdk]

Going to push as commit e25121d.
Since your change was applied there have been 6 commits pushed to the master branch:

• 5c8366e: 8268622: Performance issues in javac Name class
• ad81abd: 8317034: Remove redundant type cast in the java.util.stream package
• d7d1d42: 8316771: Krb5.java has not defined messages for all error codes
• f985006: 8309356: Read files in includedir in alphanumeric order
• a564d43: 8315692: Parallelize gc/stress/TestStressRSetCoarsening.java test
• 878d27d: 8317273: compiler/codecache/OverflowCodeCacheTest.java fails transiently on Graal

Your commit was automatically rebased without conflicts.

[openjdk]

@zhengyu123 Pushed as commit e25121d.

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