8351999: JFR: Incorrect scaling of throttled values

[egahlin]

Could I have a review of a PR that fixes an incorrect scaling of samples for the ThrottleSetting.

Testing: jdk/jdk/jfr

Thanks
Erik

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Issue

• JDK-8351999: JFR: Incorrect scaling of throttled values (Bug - P3)

Reviewers

• Aleksey Shipilev (@shipilev - Reviewer)

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8351999: JFR: Incorrect scaling of throttled values

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At the time when this comment was updated there had been 3 new commits pushed to the master branch:

• 65c5282: 8351938: C2: Print compilation bailouts with PrintCompilation compile command
• e3c29c9: 8351556: Optimize Location.locationFor/isModuleOrientedLocation
• a7a09f6: 8349632: RISC-V: Add Zfa fminm/fmaxm

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• 00: Full (ae6b3468)

[shipilev]

Reasoning from the math alone, it looks obvious that samples *= samples is not correct. So that part looks fine.

Thinking about unit.nanos == SECONDS.nanos case. This means the unit is exactly "seconds", so no adjustment is needed?

[egahlin]

Native expects the value in milliseconds, and the default value is 1000 ms, so it seems fine to me.

[egahlin]

/integrate

[openjdk]

Going to push as commit 0450ba9.
Since your change was applied there have been 16 commits pushed to the master branch:

• e5666f5: 8351976: assert(vthread_epoch == current_epoch) failed: invariant
• 2eecf15: 8351967: JFR: AnnotationIterator should handle num_annotations = 0
• c8913d2: 8345555: Improve layout of search results
• e29d405: 8352110: [BACKOUT] C2: Print compilation bailouts with PrintCompilation compile command
• 9f8d833: 8346194: Improve G1 pre-barrier C2 cost estimate
• 2672c40: 8351167: ZGC: Lazily initialize livemap
• 63bf791: 8351992: JFR: Improve robustness of the SettingControl examples
• 06289f3: 8351821: VMManagementImpl.c avoid switching off warnings
• 0460978: 8351096: Typos in Vector API doc
• 7f42804: 8350524: Some hotspot/jtreg/serviceability/dcmd/vm tier1 tests fail on static JDK
• ... and 6 more: https://git.openjdk.org/jdk/compare/0454406417701341dafa0d733cd480c145673d32...master

Your commit was automatically rebased without conflicts.

[openjdk]

@egahlin Pushed as commit 0450ba9.

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