8354517: Parallel: JDK-8339668 causes up to 3.7x slowdown in openjdk.bench.vm.gc.systemgc

[albertnetymk]

Before JDK-8339668, full-gc marking array-chunk size uses ObjArrayMarkingStride. This patch restores the old behavior (performance).

The fix is extract out the chunk-size from PartialArraySplitter and use the either ParGCArrayScanChunk or ObjArrayMarkingStride, depending on the context -- the former is used during young-gc while the latter full-gc.

Test: tier1-3; checked perf regression is gone

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Progress

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Issue

• JDK-8354517: Parallel: JDK-8339668 causes up to 3.7x slowdown in openjdk.bench.vm.gc.systemgc (Bug - P2)

Reviewers

• Thomas Schatzl (@tschatzl - Reviewer)
• Axel Boldt-Christmas (@xmas92 - Reviewer)
• Zhengyu Gu (@zhengyu123 - Reviewer)

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[bridgekeeper]

👋 Welcome back ayang! 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]

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

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

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

8354517: Parallel: JDK-8339668 causes up to 3.7x slowdown in openjdk.bench.vm.gc.systemgc

Reviewed-by: tschatzl, aboldtch, zgu

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At the time when this comment was updated there had been 15 new commits pushed to the master branch:

• 1258af4: 8357135: java.lang.OutOfMemoryError: Error creating or attaching to libjvmci after JDK-8356447
• 16d4551: 8355452: GHA: Test jtreg tier1 on linux-x64 static-jdk
• 72e440d: 8357303: (fs) UnixSecureDirectoryStream.implDelete has unused haveFlags parameter
• ... and 12 more: https://git.openjdk.org/jdk/compare/68c1d305e726f3f4d7209b857f58cc10de5c0132...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

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[openjdk]

@albertnetymk The following label will be automatically applied to this pull request:

• hotspot-gc

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[mlbridge]

Webrevs

• 00: Full (bed166af)

[zhengyu123]

Thank you for fixing it. Look good!

[albertnetymk]

Thanks for review.

/integrate

[openjdk]

Going to push as commit 36f6d15.
Since your change was applied there have been 28 commits pushed to the master branch:

• ae7ae84: 8356016: Build fails by clang(XCode 16.3) on macOS after JDK-8347719
• d6e4c5f: 8357506: [JVMCI] Consolidate eager JVMCI initialization code
• 9d9e41f: 8356894: Adjust CreateSymbols to properly handle the newly added @jdk.internal.RequiresIdentity
• ... and 25 more: https://git.openjdk.org/jdk/compare/68c1d305e726f3f4d7209b857f58cc10de5c0132...master

Your commit was automatically rebased without conflicts.

[openjdk]

@albertnetymk Pushed as commit 36f6d15.

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