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8361726: Shenandoah: More detailed evacuation instrumentation #26222

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@earthling-amzn earthling-amzn commented Jul 9, 2025 •
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Shenandoah has not product instrumentation to track evacuation performance. This change introduces more detail by categorizing each evacuation as young, old or promotion.

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  • JDK-8361726: Shenandoah: More detailed evacuation instrumentation (Enhancement - P4)

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bridgekeeper bot commented Jul 9, 2025

👋 Welcome back wkemper! 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.

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openjdk bot commented Jul 9, 2025 •
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@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:

8361726: Shenandoah: More detailed evacuation instrumentation

Reviewed-by: ysr, kdnilsen

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

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@openjdk openjdk bot added the rfr Pull request is ready for review label Jul 9, 2025
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openjdk bot commented Jul 9, 2025

@earthling-amzn 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.

@openjdk openjdk bot added hotspot-gc hotspot-gc-dev@openjdk.org shenandoah shenandoah-dev@openjdk.org labels Jul 9, 2025
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kdnilsen
kdnilsen approved these changes Jul 22, 2025
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Thanks. This instrumentation is helpful in evaluating further proposed changes.

ysramakrishna
ysramakrishna approved these changes Jul 23, 2025
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Approved, modulo a few nits.

The extra detail is useful!

Shenandoah has product only instrumentation to track evacuation performance.

Did you mean to say non-product instead of product only above?

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openjdk bot commented Jul 23, 2025

@earthling-amzn this pull request can not be integrated into master due to one or more merge conflicts. To resolve these merge conflicts and update this pull request you can run the following commands in the local repository for your personal fork:

git checkout categorize-evacuations
git fetch https://git.openjdk.org/jdk.git master
git merge FETCH_HEAD
# resolve conflicts and follow the instructions given by git merge
git commit -m "Merge master"
git push

@openjdk openjdk bot added the merge-conflict Pull request has merge conflict with target branch label Jul 23, 2025
@openjdk openjdk bot removed the merge-conflict Pull request has merge conflict with target branch label Jul 23, 2025
ysramakrishna
ysramakrishna reviewed Jul 24, 2025
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src/hotspot/share/gc/shenandoah/shenandoahEvacTracker.hpp Outdated
// Record that the given thread has begun to evacuate an object of this size.
void begin_evacuation(Thread* thread, size_t bytes, ShenandoahAffiliation from, ShenandoahAffiliation to);

// Multiple threads may attempt to evacuate the same object, but only the succeeding thread will end the evacuation.
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Instead of only the succeeding thread will end the evacuation, I might say: the unique thread that is successful will end the evacuation. (Alternatively, replace "succeeding" with "successful"; the word "succeeding" as an adjective can be ambiguous in this context.)

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earthling-amzn commented Jul 24, 2025

GHA failure on macos looks unrelated (test was running G1).

/integrate

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@earthling-amzn This pull request has not yet been marked as ready for integration.

@openjdk openjdk bot added the ready Pull request is ready to be integrated label Jul 25, 2025
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earthling-amzn commented Jul 25, 2025

/integrate

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openjdk bot commented Jul 25, 2025

Going to push as commit e756c0d.
Since your change was applied there have been 20 commits pushed to the master branch:

Your commit was automatically rebased without conflicts.

@openjdk openjdk bot added the integrated Pull request has been integrated label Jul 25, 2025
@openjdk openjdk bot closed this Jul 25, 2025
@openjdk openjdk bot removed ready Pull request is ready to be integrated rfr Pull request is ready for review labels Jul 25, 2025
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openjdk bot commented Jul 25, 2025

@earthling-amzn Pushed as commit e756c0d.

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

@earthling-amzn earthling-amzn deleted the categorize-evacuations branch October 7, 2025 17:05
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@kdnilsen kdnilsen kdnilsen approved these changes

@ysramakrishna ysramakrishna ysramakrishna approved these changes

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