8337493: [JVMCI] Number of libgraal threads might be too low

[rmosaner]

The -XX:JVMCINativeLibraryThreadFraction flag defines the ratio between JVMCI threads and C1 threads.
With a default value of 0.33 the number of JVMCI threads is significantly smaller than the number of C2 threads would be.

This can lead to unexpected warmup behavior with -XX:+UseJVMCICompiler. This PR changes the default value of -XX:JVMCINativeLibraryThreadFraction to yield the same number of JVMCI threads as C2 threads.

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Progress

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Issue

• JDK-8337493: [JVMCI] Number of libgraal threads might be too low (Enhancement - P4)

Reviewers

• Doug Simon (@dougxc - Reviewer)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/21279/head:pull/21279
$ git checkout pull/21279

Update a local copy of the PR:
$ git checkout pull/21279
$ git pull https://git.openjdk.org/jdk.git pull/21279/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 21279

View PR using the GUI difftool:
$ git pr show -t 21279

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Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/21279.diff

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[bridgekeeper]

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[openjdk]

@rmosaner 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:

8337493: [JVMCI] Number of libgraal threads might be too low

Reviewed-by: dnsimon

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At the time when this comment was updated there had been 2 new commits pushed to the master branch:

• 2dc3b1a: 8341201: Broken link in AbstractAnnotationValueVisitor7 due to extra quotation mark
• ad5ffcc: 8341168: Cleanup dead code after JDK-8322630

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[openjdk]

@rmosaner The following labels will be automatically applied to this pull request:

• graal
• hotspot-compiler

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[mlbridge]

Webrevs

• 00: Full (9e0a3188)

[dougxc]

LGTM.

[rmosaner]

/integrate

[openjdk]

@rmosaner
Your change (at version 9e0a318) is now ready to be sponsored by a Committer.

[dougxc]

/sponsor

[openjdk]

Going to push as commit 7cc7c08.
Since your change was applied there have been 3 commits pushed to the master branch:

• f7c7958: 8340420: ZGC: Should call vm_shutdown_during_initialization if initialization fails
• 2dc3b1a: 8341201: Broken link in AbstractAnnotationValueVisitor7 due to extra quotation mark
• ad5ffcc: 8341168: Cleanup dead code after JDK-8322630

Your commit was automatically rebased without conflicts.

[openjdk]

@dougxc @rmosaner Pushed as commit 7cc7c08.

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