On Thu, 16 Feb 2023 21:41:12 GMT, Sergey Bylokhov <s...@openjdk.org> wrote:
>> The test has become unstable recently, there were quite a few failures, on
>> Windows mostly. I was lucky enough to find a host where the test failed
>> consistently.
>>
>> I call `System.gc()` directly as suggested in comments to the bug. I used
>> `PhantomReference` instead of `WeakReference`.
>>
>> Now the test calls `System.gc()` in a loop and waits for the reference to be
>> enqueued. In majority of cases, the test exits the loop at the second
>> attempt.
>
> test/jdk/java/awt/List/ListGarbageCollectionTest/AwtListGarbageCollectionTest.java
> line 72:
>
>> 70: do {
>> 71: System.out.println("Attempt " + count);
>> 72: System.gc();
>
> As far as I remember the call of System.gc() could be ignored, and the only
> way to trigger GC is to trigger the OOM. Probably we can combine
> referenceQueue.remove(ENQUEUE_TIMEOUT) + OOM?
For this reason, GC logs are enabled. If, for whatever reason, the call to
`System.gc()` is ignored, we'll see it in the test log. Then a specific GC
could be selected, for example, or another fix implemented.
OOME does not guarantee a full GC cycle either.
Having the above in mind, I'd rather keep it simple.
-------------
PR: https://git.openjdk.org/jdk/pull/12594
