8326446: The User and System of jdk.CPULoad on Apple M1 are inaccurate

[yanglong1010]

Hi, all

Could I have a review of this backport.

This pull request contains a backport of commit 8dbd4b391f7deb1a46a5f07f0bc46f23d6715ddb from the openjdk/jdk repository.

Testing: I ran test/jdk/jdk/jfr/event/os/TestCPULoad.java and passed. All GHA tests are passed (except linux-cross-compile, build(riscv64), Create sysroot. It looks like there's an issue with the GHA's process).

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8326446 needs maintainer approval

Issue

• JDK-8326446: The User and System of jdk.CPULoad on Apple M1 are inaccurate (Bug - P3 - Approved)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u-dev.git pull/341/head:pull/341
$ git checkout pull/341

Update a local copy of the PR:
$ git checkout pull/341
$ git pull https://git.openjdk.org/jdk21u-dev.git pull/341/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 341

View PR using the GUI difftool:
$ git pr show -t 341

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk21u-dev/pull/341.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back yanglong1010! 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.

[openjdk]

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

[openjdk]

⚠️ @yanglong1010 This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[mlbridge]

Webrevs

• 00: Full (5c8cbfa6)

[yanglong1010]

/approval 8326446 request The JFR's jdk.CPULoad event provides information about how much CPU is occupied by Java process, often used in performance analysis. But the User and System percentages of jdk.CPULoad event on Apple M1 are inaccurate (far below normal). I would like to backport this fix to jdk21u-dev.
Low risk: This patch only affects the User and System percentages JFR's jdk.CPULoad event.
Testing: I ran test/jdk/jdk/jfr/event/os/TestCPULoad.java and passed. All GHA tests are passed (except linux-cross-compile, build(riscv64), Create sysroot. It looks like there's an issue with the GHA's process).

[openjdk]

@yanglong1010
8326446: The approval request has been created successfully.

[openjdk]

@yanglong1010 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:

8326446: The User and System of jdk.CPULoad on Apple M1 are inaccurate

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 7 new commits pushed to the master branch:

• 3086ed8: 8324834: Use _LARGE_FILES on AIX
• 83cc4cb: 8327059: os::Linux::print_proc_sys_info add swappiness information
• 624e603: 8315834: Open source several Swing JSpinner related tests
• 066af44: 8325137: com/sun/management/ThreadMXBean/ThreadCpuTimeArray.java can fail in Xcomp with out of expected range
• 8e439ba: 8317287: [macos14] InterJVMGetDropSuccessTest.java: Child VM: abnormal termination
• 9a8d91a: 8315677: Open source few swing JFileChooser and other tests
• c4c4b22: 8325326: [PPC64] Don't relocate in case of allocation failure

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

As you do not have Committer status in this project an existing Committer must agree to sponsor your change.

➡️ To flag this PR as ready for integration with the above commit message, type /integrate in a new comment. (Afterwards, your sponsor types /sponsor in a new comment to perform the integration).

[yanglong1010]

Could I have sponsor of this backport ? I would appreciate it very much.

[DamonFool]

/sponsor

[openjdk]

@DamonFool The change author (@yanglong1010) must issue an integrate command before the integration can be sponsored.

[yanglong1010]

/integrate

[DamonFool]

/sponsor

[openjdk]

@yanglong1010
Your change (at version 5c8cbfa) is now ready to be sponsored by a Committer.

[openjdk]

Going to push as commit 50f447c.
Since your change was applied there have been 7 commits pushed to the master branch:

• 3086ed8: 8324834: Use _LARGE_FILES on AIX
• 83cc4cb: 8327059: os::Linux::print_proc_sys_info add swappiness information
• 624e603: 8315834: Open source several Swing JSpinner related tests
• 066af44: 8325137: com/sun/management/ThreadMXBean/ThreadCpuTimeArray.java can fail in Xcomp with out of expected range
• 8e439ba: 8317287: [macos14] InterJVMGetDropSuccessTest.java: Child VM: abnormal termination
• 9a8d91a: 8315677: Open source few swing JFileChooser and other tests
• c4c4b22: 8325326: [PPC64] Don't relocate in case of allocation failure

Your commit was automatically rebased without conflicts.

[openjdk]

@DamonFool @yanglong1010 Pushed as commit 50f447c.

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

[yanglong1010]

Thank you all.