On Mon, 15 Dec 2025 11:32:00 GMT, Viktor Klang <[email protected]> wrote:
>> Doug Lea has updated the pull request incrementally with one additional
>> commit since the last revision:
>>
>> Adjust runworker for previous update
>
> src/java.base/share/classes/java/util/concurrent/ForkJoinPool.java line 1865:
>
>> 1863: long ac = (c + RC_UNIT) & RC_MASK, nc;
>> 1864: int sp = (int)c, i = sp & SMASK;
>> 1865: if ((short)(c >>> RC_SHIFT) >= pc)
>
> I'm wondering if it might make sense to re-read `parallelism` on each new
> loop, since if we have a parallelism resize *during this loop* we want to
> exit early?
>
>
> Suggestion:
>
> for (long c = ctl;;) {
> WorkQueue[] qs = queues;
> long ac = (c + RC_UNIT) & RC_MASK, nc;
> int sp = (int)c, i = sp & SMASK, pc;
> if ((short)(c >>> RC_SHIFT) >= (pc = parallelism))
Maybe but it should also be rare to adjust parallelism, and setParallelism
changed recently to signal.
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PR Review Comment: https://git.openjdk.org/jdk/pull/28797#discussion_r2619087486
