[jdk25u-dev] RFR: 8359868: Shenandoah: Free threshold heuristic does not use SoftMaxHeapSize

[Y. Srinivas Ramakrishna]

On Wed, 28 Jan 2026 20:02:00 GMT, William Kemper <wkemper at openjdk.org> wrote:

> Not clean, but conflicts were trivial to resolve. We have been running versions of this patch in production for months now.

This backport LGTM as is, but left a comment re possible cleanup in tip.

src/hotspot/share/gc/shenandoah/shenandoahMetrics.cpp line 67:

> 65:   // of the generation capacity to determine whether the available memory within the generation exceeds the
> 66:   // critical threshold.
> 67:   size_t free_expected = (ShenandoahHeap::heap()->soft_max_capacity() / 100) * ShenandoahCriticalFreeThreshold;

I realize this is a backport, so no changes are necessary in this one, but it would make sense to fix this in upstream by removing the confusing remaining references -- and the unnecessary and unused generation parameter.

The cleanup can be done in tip in a separate ticket. cc @rgithubli

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Marked as reviewed by ysr (Reviewer).

PR Review: https://git.openjdk.org/jdk25u-dev/pull/195#pullrequestreview-3725996562
PR Review Comment: https://git.openjdk.org/jdk25u-dev/pull/195#discussion_r2744348817