jmx-dev RFR: 8354407: Test com/sun/management/OperatingSystemMXBean/GetProcessCpuLoad.java still fails on Windows

[Chris Plummer]

On Wed, 30 Apr 2025 11:13:53 GMT, Kevin Walls <kevinw at openjdk.org> wrote:

> This is hard to reproduce, and at first I'd only seen -1 returned on the first calls to mbean.getProcessCpuLoad().
> But eventually I observed a -1 at any time, including in middle of the iterations, or on the last iteration which makes the current test fail.
> 
> Should fail on Windows only if we only ever see -1 returned from getProcessCpuLoad().
> Remove the "exclusiveAccess.dirs=." (JDK-8353231 adding "exclusiveAccess.dirs=." did not fix this.)

test/jdk/com/sun/management/OperatingSystemMXBean/GetProcessCpuLoad.java line 60:

> 58:                 // A good reading: forget any previous -1.
> 59:                 ex = null;
> 60:                 good++;

The `ex = null` is a little misleading because actually it's irrelevant. An error on the next iteration will set it again, but it will be ignored because `good != 0`.

test/jdk/com/sun/management/OperatingSystemMXBean/GetProcessCpuLoad.java line 69:

> 67:         }
> 68: 
> 69:         if (good == 0 && ex != null) {

The check for `ex != null` is not necessary. It should always be set if `good == 0`

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/24961#discussion_r2069176907
PR Review Comment: https://git.openjdk.org/jdk/pull/24961#discussion_r2069176999