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

[Long Yang]

On Fri, 23 Feb 2024 07:49:45 GMT, Long Yang <duke at openjdk.org> wrote:

> hi
> 
> I would like to fix this.
> 
> As the description in [JDK-8326446](https://bugs.openjdk.org/browse/JDK-8326446).
> JFR uses task_info() with flavor TASK_ABSOLUTETIME_INFO to read User and System time. it is not reliable on Apple m1.
> 
> Libc provides the [times](https://man7.org/linux/man-pages/man2/times.2.html) function, which uses TASK_BASIC_INFO_COUNT and TASK_THREAD_TIMES_INFO_COUNT. It will also return the real time of the process, and the time unit is the same, which is suitable for solving this problem.
> 
> I ran test/jdk/jdk/jfr/event/os/TestCPULoad.java and passed.
> 
> I would appreciate it if you could review this.

This pull request has now been integrated.

Changeset: 8dbd4b39
Author:    yibo.yl <yibo.yl at alibaba-inc.com>
Committer: Denghui Dong <ddong at openjdk.org>
URL:       https://git.openjdk.org/jdk/commit/8dbd4b391f7deb1a46a5f07f0bc46f23d6715ddb
Stats:     30 lines in 1 file changed: 1 ins; 7 del; 22 mod

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

Reviewed-by: mgronlun, egahlin

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PR: https://git.openjdk.org/jdk/pull/17976