RFR: 8374364: TestCgroupMetrics.java fails when cpuset unmounted [v4]

[David Holmes]

On Mon, 29 Dec 2025 08:48:15 GMT, SendaoYan <syan at openjdk.org> wrote:

>> Hi all,
>> 
>> Test jdk/internal/platform/cgroup/TestCgroupMetrics.java report fails when the cpuset unmounted. The details shows in jbs issue. I think it's better to check the 'cpu period' or 'cpuset' available or not before run the releated tests.
>> 
>> Change has been verified locally. Test-fix only, no risk.
>
> SendaoYan has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Update copyright year for test/lib/jdk/test/lib/containers/cgroup/MetricsTesterCgroupV1.java

A couple of comments but I'm not sure what the right approach is here. Seems inconsistent to use SkippedException in one place, but not others.

test/lib/jdk/test/lib/containers/cgroup/MetricsTester.java line 87:

> 85:     public static void main(String[] args) throws Exception {
> 86:         Metrics m = Metrics.systemMetrics();
> 87:         // If cgroups is not configured, report success

Suggestion:

        // If cgroups is not configured, the test is skipped.

test/lib/jdk/test/lib/containers/cgroup/MetricsTesterCgroupV1.java line 373:

> 371:         long oldVal = metrics.getCpuPeriod();
> 372:         if (oldVal == CgroupSubsystem.LONG_RETVAL_UNLIMITED) {
> 373:             System.out.println("Get cpu period fails, test skipped.");

Note sure this indicates a "fail" as such.

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PR Review: https://git.openjdk.org/jdk/pull/28996#pullrequestreview-3629079111
PR Review Comment: https://git.openjdk.org/jdk/pull/28996#discussion_r2663353307
PR Review Comment: https://git.openjdk.org/jdk/pull/28996#discussion_r2663359000