JDK-8306768: CodeCache Analytics reports wrong threshold

[AntonKozlov]

Jcmd CodeCache_Analytics uses own implementation of threshold calculation, allowing an error to creep in, making report invalid. The suggestion is to use the existing method for free ratio calculation. After the fix, the reported values become sane.

java -XX:InitialCodeCacheSize=1G -XX:ReservedCodeCacheSize=1G ...

cmd jdk.compiler/com.sun.tools.javac.launcher.Main  Compiler.CodeHeap_Analytics | grep -A 2 "Threshold for method to be considered 'cold'"

Threshold for method to be considered 'cold':    -2037.960
min. hotness =   1016
avg. hotness =   2048
--
Threshold for method to be considered 'cold':    -2037.960
min. hotness =   1016
avg. hotness =   2048
--
Threshold for method to be considered 'cold':    -2037.960
No hotness data available

---

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Issue

• JDK-8306768: CodeCache Analytics reports wrong threshold

Reviewers

• Paul Hohensee (@phohensee - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back akozlov! 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.

[mlbridge]

Webrevs

• 00: Full (d1bb171c)

[phohensee]

Lgtm.

[openjdk]

@AntonKozlov 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:

8306768: CodeCache Analytics reports wrong threshold

Reviewed-by: phh

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 8 new commits pushed to the master branch:

• e132605: 8296545: C2 Blackholes should allow load optimizations
• d5cbf22: 8306658: GHA: MSVC installation could be optional since it might already be pre-installed
• bf0606a: 8283566: G1: Improve G1BarrierSet::enqueue performance
• e6e6bed: 8252990: Intrinsify Unsafe.storeStoreFence
• 24e91c1: 8302594: use-after-free in Node::destruct
• d964229: 8302172: [JVMCI] HotSpotResolvedJavaMethodImpl.canBeInlined must respect ForceInline
• 3e0e4f0: 8301338: Identical branch conditions in CompileBroker::print_heapinfo
• ee63f83: 8296412: Special case infinite loops with unmerged backedges in IdealLoopTree::check_safepts

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
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[AntonKozlov]

Thanks for review! The bug is also approved by the label.

/integrate

[openjdk]

@AntonKozlov
Your change (at version d1bb171) is now ready to be sponsored by a Committer.

[phohensee]

/sponsor

[openjdk]

Going to push as commit 243e643.
Since your change was applied there have been 8 commits pushed to the master branch:

• e132605: 8296545: C2 Blackholes should allow load optimizations
• d5cbf22: 8306658: GHA: MSVC installation could be optional since it might already be pre-installed
• bf0606a: 8283566: G1: Improve G1BarrierSet::enqueue performance
• e6e6bed: 8252990: Intrinsify Unsafe.storeStoreFence
• 24e91c1: 8302594: use-after-free in Node::destruct
• d964229: 8302172: [JVMCI] HotSpotResolvedJavaMethodImpl.canBeInlined must respect ForceInline
• 3e0e4f0: 8301338: Identical branch conditions in CompileBroker::print_heapinfo
• ee63f83: 8296412: Special case infinite loops with unmerged backedges in IdealLoopTree::check_safepts

Your commit was automatically rebased without conflicts.

[openjdk]

@phohensee @AntonKozlov Pushed as commit 243e643.

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