RFR: 8209595: MonitorVmStartTerminate.java timed out [v2]

[Serguei Spitsyn]

On Fri, 20 Oct 2023 13:28:19 GMT, Kevin Walls <kevinw at openjdk.org> wrote:

>> From studying test failures, it looks like the way the test identifies its related processes is failing.
>> It checks the mainArgs of a process by attaching, and looks like it occasionally misses getting a valid match.  The hasMainArgs method ignores exceptions as it is expecting some exceptions: it is going to test unrelated java process which happen to start.
>> 
>> It should retry this main args check on failure, but not too many times to be a burden on other valid unrelated processes, and should also log the PIDs that have an issue so we can see if this is part of any future failure.
>> 
>> Other small logging changes so we can see more easily the progress through the test.
>
> Kevin Walls has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains six additional commits since the last revision:
> 
>  - Check main args fetching was ok.  Increase sleep.
>  - nits
>  - Merge remote-tracking branch 'upstream/master' into MonitorVmStartTerminate
>  - nit1
>  - Comment, and move takeNap() sleep method.
>  - 8209595: MonitorVmStartTerminate.java timed out

Looks good.
Placed a couple of nits.
Thanks,
Serguei

test/jdk/sun/jvmstat/monitor/MonitoredVm/MonitorVmStartTerminate.java line 183:

> 181:             // As we have seen test timeouts due to missing a notification,
> 182:             // we should retry this attempt to check arguments for a match.
> 183:             for (int i=0; i<ARGS_ATTEMPTS; i++) {

Nit: Need spaces around `=` and `<`.

test/jdk/sun/jvmstat/monitor/MonitoredVm/MonitorVmStartTerminate.java line 199:

> 197:                     System.out.println("hasMainArgs(" + id + "): " + e);
> 198:                 }
> 199:                 takeNap();

Nit: I'm thinking if moving this after line 197 would be more clear.

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

Marked as reviewed by sspitsyn (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/16077#pullrequestreview-1665950516
PR Review Comment: https://git.openjdk.org/jdk/pull/16077#discussion_r1351289715
PR Review Comment: https://git.openjdk.org/jdk/pull/16077#discussion_r1351291242