8328075: Shenandoah: Avoid forwarding when objects don't move in full-GC

[pengxiaolong]

---

Progress

• Change must not contain extraneous whitespace
• JDK-8328075 needs maintainer approval
• Commit message must refer to an issue

Issue

• JDK-8328075: Shenandoah: Avoid forwarding when objects don't move in full-GC (Enhancement - P4 - Approved)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk17u-dev.git pull/2474/head:pull/2474
$ git checkout pull/2474

Update a local copy of the PR:
$ git checkout pull/2474
$ git pull https://git.openjdk.org/jdk17u-dev.git pull/2474/head

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Checkout this PR locally:
$ git pr checkout 2474

View PR using the GUI difftool:
$ git pr show -t 2474

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Download this PR as a diff file:
https://git.openjdk.org/jdk17u-dev/pull/2474.diff

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[bridgekeeper]

Hi @pengxialong, welcome to this OpenJDK project and thanks for contributing!

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[openjdk]

@pengxiaolong 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:

8328075: Shenandoah: Avoid forwarding when objects don't move in full-GC

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 39 new commits pushed to the master branch:

• 5cdff9f: 8318474: Fix memory reporter for thread_count
• a058ad1: 8315362: NMT: summary diff reports threads count incorrectly
• 9eb9702: 8331164: createJMHBundle.sh download jars fail when url needed to be redirected
• 46ba9bb: 8318479: [jmh] the test security.CacheBench failed for multiple threads run
• 1de0c0a: 8256291: RunThese30M fails "assert(_class_unload ? true : ((((JfrTraceIdBits::load(class_loader_klass)) & ((1 << 4) << 8)) != 0))) failed: invariant"
• eebb80c: 8317288: [macos] java/awt/Window/Grab/GrabTest.java: Press on the outside area didn't cause ungrab
• cc0c143: 8310108: Skip ReplaceCriticalClassesForSubgraphs when EnableJVMCI is specified
• 7a8cf6c: 8319713: Parallel: Remove PSAdaptiveSizePolicy::should_full_GC
• 515bc9a: 8318986: Improve GenericWaitBarrier performance
• dcb2c35: 8295111: dpkg appears to have problems resolving symbolically linked native libraries
• ... and 29 more: https://git.openjdk.org/jdk17u-dev/compare/68caeca1a5f265ca30a7e6d2a62127d458a3473e...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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➡️ To flag this PR as ready for integration with the above commit message, type /integrate in a new comment. (Afterwards, your sponsor types /sponsor in a new comment to perform the integration).

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[pengxiaolong]

/covered

[bridgekeeper]

Thank you! Please allow for a few business days to verify that your employer has signed the OCA. Also, please note that pull requests that are pending an OCA check will not usually be evaluated, so your patience is appreciated!

[openjdk]

⚠️ @pengxialong This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[mlbridge]

Webrevs

• 01: Full - Incremental (a5bbae4f)
• 00: Full (214c6c1c)

[openjdk]

@pengxialong usage: /approval [<id>] (request|cancel) [<text>]

[pengxiaolong]

/approval JDK-8328075 request

[openjdk]

@pengxialong
JDK-8328075: The approval request has been created successfully.

[openjdk]

@pengxiaolong
Your change (at version a5bbae4) is now ready to be sponsored by a Committer.

[TheRealMDoerr]

/sponsor

[openjdk]

Going to push as commit 235baaa.
Since your change was applied there have been 39 commits pushed to the master branch:

• 5cdff9f: 8318474: Fix memory reporter for thread_count
• a058ad1: 8315362: NMT: summary diff reports threads count incorrectly
• 9eb9702: 8331164: createJMHBundle.sh download jars fail when url needed to be redirected
• 46ba9bb: 8318479: [jmh] the test security.CacheBench failed for multiple threads run
• 1de0c0a: 8256291: RunThese30M fails "assert(_class_unload ? true : ((((JfrTraceIdBits::load(class_loader_klass)) & ((1 << 4) << 8)) != 0))) failed: invariant"
• eebb80c: 8317288: [macos] java/awt/Window/Grab/GrabTest.java: Press on the outside area didn't cause ungrab
• cc0c143: 8310108: Skip ReplaceCriticalClassesForSubgraphs when EnableJVMCI is specified
• 7a8cf6c: 8319713: Parallel: Remove PSAdaptiveSizePolicy::should_full_GC
• 515bc9a: 8318986: Improve GenericWaitBarrier performance
• dcb2c35: 8295111: dpkg appears to have problems resolving symbolically linked native libraries
• ... and 29 more: https://git.openjdk.org/jdk17u-dev/compare/68caeca1a5f265ca30a7e6d2a62127d458a3473e...master

Your commit was automatically rebased without conflicts.

[openjdk]

@TheRealMDoerr @pengxiaolong Pushed as commit 235baaa.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.