8365571: GenShen: PLAB promotions may remain disabled for evacuation threads

[earthling-amzn]

Clean backport. Fixes performance issue in generational mode for Shenanodah.

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Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8365571: GenShen: PLAB promotions may remain disabled for evacuation threads (Bug - P4)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/shenandoah-jdk21u.git pull/214/head:pull/214
$ git checkout pull/214

Update a local copy of the PR:
$ git checkout pull/214
$ git pull https://git.openjdk.org/shenandoah-jdk21u.git pull/214/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 214

View PR using the GUI difftool:
$ git pr show -t 214

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/shenandoah-jdk21u/pull/214.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

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[openjdk]

@earthling-amzn 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:

8365571: GenShen: PLAB promotions may remain disabled for evacuation threads

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 1 new commit pushed to the master branch:

• 87538c5: 8361948: Shenandoah: region free capacity unit mismatch

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[openjdk]

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

[mlbridge]

Webrevs

• 00: Full (ffaab0dc)

[earthling-amzn]

/integrate

[openjdk]

Going to push as commit dcf0b23.
Since your change was applied there has been 1 commit pushed to the master branch:

• 87538c5: 8361948: Shenandoah: region free capacity unit mismatch

Your commit was automatically rebased without conflicts.

[openjdk]

@earthling-amzn Pushed as commit dcf0b23.

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