On Wed, 29 Oct 2025 06:17:19 GMT, SendaoYan <[email protected]> wrote:
>> Hi all,
>>
>> We observed the test
>> vmTestbase/nsk/jvmti/AttachOnDemand/attach020/TestDescription.java
>> intermittent fails. since the target application intermittent OOM. The
>> target application will try to exhaust the heap memory and then trigger
>> garbage collection by `ClassUnloader.eatMemory()` in file
>> test/hotspot/jtreg/vmTestbase/nsk/jvmti/AttachOnDemand/attach020/attach020Target.java.
>>
>> So I think it's better to limited the max heap usage of target application.
>> Before this PR, the physical memory usage is about 30.7GB(this depends the
>> total free memory on the test machine), and the jtreg main action take about
>> 11 seconds to finish; After this PR, the physical memory usage is about
>> 126MB, and the jtreg main action take about 0.7 senonds to finish. I use
>> below command to get the usage of physical memory.
>>
>> Change has been verified locally, test-fix only, no risk.
>>
>>
>> grep VmRSS /proc/`ps -ef | grep -w java | grep vmsqe.aod.AppId | awk '{print
>> $2}'`/status
>
> SendaoYan has updated the pull request incrementally with one additional
> commit since the last revision:
>
> Remove unnecessary try/catch and loop
Sorry, I missed first time. See my comment about `import
nsk.share.ClassUnloader;` inline.
test/hotspot/jtreg/vmTestbase/nsk/jvmti/AttachOnDemand/attach022/attach022Target.java
line 51:
> 49:
> 50: log.display("Provoking GC");
> 51: WhiteBox.getWhiteBox().fullGC();
Please also remove lines
`import nsk.share.ClassUnloader;`
ssince this class is not using anymore.
-------------
Changes requested by lmesnik (Reviewer).
PR Review: https://git.openjdk.org/jdk/pull/28011#pullrequestreview-3397245800
PR Review Comment: https://git.openjdk.org/jdk/pull/28011#discussion_r2476258933
