Integrated: 8365571: GenShen: PLAB promotions may remain disabled for evacuation threads

[William Kemper]

On Thu, 14 Aug 2025 18:15:00 GMT, William Kemper <wkemper at openjdk.org> wrote:

> Mutators and GC workers have old generation LABs for promotions and old generation evacuations. Priority is given to old evacuations by using a promotion budget. Once the promotion budget is exhausted, a thread local flag is set to disable further promotions (the LAB can still be used for old evacuations). This thread local flag is meant to be cleared to allow all threads to resume promotions on the next cycle. However, this flag is only reset for workers that perform thread root evacuations, which may not be the same workers that perform subsequent evacuations. This patch clears the flag for all threads when their LABs are retired at the end of evacuation.

This pull request has now been integrated.

Changeset: 08db4b99
Author:    William Kemper <wkemper at openjdk.org>
URL:       https://git.openjdk.org/jdk/commit/08db4b99622e488558dd7987c34f1c515fa30426
Stats:     24 lines in 2 files changed: 5 ins; 15 del; 4 mod

8365571: GenShen: PLAB promotions may remain disabled for evacuation threads

Reviewed-by: kdnilsen, ysr, shade

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PR: https://git.openjdk.org/jdk/pull/26785