On Wed, 22 May 2024 15:32:42 GMT, Doug Lea <d...@openjdk.org> wrote:
>> This set of changes address causes of poor utilization with small numbers of
>> cores due to overly aggressive contention avoidance. A number of further
>> adjustments were needed to still avoid most contention effects in
>> deployments with large numbers of cores
>
> Doug Lea 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 36 additional commits since
> the last revision:
>
> - Merge branch 'openjdk:master' into JDK-8322732
> - More performance tradoffs
> - Address review comments
> - Merge branch 'openjdk:master' into JDK-8322732
> - Repack some fields; adjust control flow
> - Merge branch 'openjdk:master' into JDK-8322732
> - Next version
> - Merge branch 'openjdk:master' into JDK-8322732
> - Reduce unneeded signals
> - Merge branch 'openjdk:master' into JDK-8322732
> - ... and 26 more: https://git.openjdk.org/jdk/compare/d5552864...f1fc4f3e
src/java.base/share/classes/java/util/concurrent/ForkJoinPool.java line 1440:
> 1438: while (task != null) {
> 1439: task.doExec();
> 1440: task = nextLocalTask(fifo);
Clean! 👍
src/java.base/share/classes/java/util/concurrent/ForkJoinPool.java line 1884:
> 1882: else
> 1883: nc = (v.stackPred & LMASK) | (c & TC_MASK);
> 1884: if (c == (c = compareAndExchangeCtl(c, nc | ac))) {
So the TTAS wasn't worth it on some architectures? 🤔
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/19131#discussion_r1610244875
PR Review Comment: https://git.openjdk.org/jdk/pull/19131#discussion_r1610245643
