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

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u-dev.git pull/575/head:pull/575
$ git checkout pull/575

Update a local copy of the PR:
$ git checkout pull/575
$ git pull https://git.openjdk.org/jdk21u-dev.git pull/575/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 575

View PR using the GUI difftool:
$ git pr show -t 575

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk21u-dev/pull/575.diff

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[bridgekeeper]

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

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[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]

@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 44 new commits pushed to the master branch:

• 9971c63: 8307788: vmTestbase/gc/gctests/LargeObjects/large003/TestDescription.java timed out
• 97c01b1: 8317288: [macos] java/awt/Window/Grab/GrabTest.java: Press on the outside area didn't cause ungrab
• 9326d88: 8310108: Skip ReplaceCriticalClassesForSubgraphs when EnableJVMCI is specified
• 87670e7: 8311666: Disabled tests in test/jdk/sun/java2d/marlin
• 56fdca3: 8316328: Test jdk/jfr/event/oldobject/TestSanityDefault.java times out for some heap sizes
• 0d0cf83: 8331746: Create a test to verify that the cmm id is not ignored
• aa66422: 8333093: Incorrect comment in zAddress_aarch64.cpp
• fb7713d: 8331714: Make OopMapCache installation lock-free
• a3b14cf: 8330576: ZYoungCompactionLimit should have range check
• 9fcb4cd: 8318479: [jmh] the test security.CacheBench failed for multiple threads run
• ... and 34 more: https://git.openjdk.org/jdk21u-dev/compare/035e3144674d494919283941a2e1f3f6dddefaeb...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.

As you do not have Committer status in this project an existing Committer must agree to sponsor your change.

➡️ 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.

[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 (c061eba9)
• 00: Full (4435c6d6)

[pengxiaolong]

/approval JDK-8328075 request backport to jdk21

[openjdk]

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

[openjdk]

⚠️ @pengxiaolong the full name on your profile does not match the author name in this pull requests' HEAD commit. If this pull request gets integrated then the author name from this pull requests' HEAD commit will be used for the resulting commit. If you wish to push a new commit with a different author name, then please run the following commands in a local repository of your personal fork:

$ git checkout JDK-8328075
$ git commit --author='Preferred Full Name <you@example.com>' --allow-empty -m 'Update full name'
$ git push

[pengxiaolong]

/integrate

[openjdk]

@pengxiaolong
Your change (at version c061eba) is now ready to be sponsored by a Committer.

[shipilev]

/sponsor

[openjdk]

Going to push as commit dc8b95f.
Since your change was applied there have been 44 commits pushed to the master branch:

• 9971c63: 8307788: vmTestbase/gc/gctests/LargeObjects/large003/TestDescription.java timed out
• 97c01b1: 8317288: [macos] java/awt/Window/Grab/GrabTest.java: Press on the outside area didn't cause ungrab
• 9326d88: 8310108: Skip ReplaceCriticalClassesForSubgraphs when EnableJVMCI is specified
• 87670e7: 8311666: Disabled tests in test/jdk/sun/java2d/marlin
• 56fdca3: 8316328: Test jdk/jfr/event/oldobject/TestSanityDefault.java times out for some heap sizes
• 0d0cf83: 8331746: Create a test to verify that the cmm id is not ignored
• aa66422: 8333093: Incorrect comment in zAddress_aarch64.cpp
• fb7713d: 8331714: Make OopMapCache installation lock-free
• a3b14cf: 8330576: ZYoungCompactionLimit should have range check
• 9fcb4cd: 8318479: [jmh] the test security.CacheBench failed for multiple threads run
• ... and 34 more: https://git.openjdk.org/jdk21u-dev/compare/035e3144674d494919283941a2e1f3f6dddefaeb...master

Your commit was automatically rebased without conflicts.

[openjdk]

@shipilev @pengxiaolong Pushed as commit dc8b95f.

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