RFR: 8342927: GenShen: Guarantee slices of time for coalesce and filling

[Kelvin Nilsen]

On Thu, 24 Oct 2024 00:13:11 GMT, William Kemper <wkemper at openjdk.org> wrote:

> By design, young collections may preempt old collections. However, in some cases, this leads to starvation of old collection cycles. When old generation collections cannot make progress, the system continues to get "backed up" until an eventual degenerated or full GC cleans out the old generation. Genshen already has a mechanism to guarantee progress for old marking. It should be extended to also provide for coalescing and filling.

Super.  Thanks.

src/hotspot/share/gc/shenandoah/shenandoah_globals.hpp line 561:

> 559:                                                                             \
> 560:   product(uintx, ShenandoahMinimumOldTimeMs, 100, EXPERIMENTAL,         \
> 561:          "Minimum amount of time in milliseconds to run old marking "       \

May want to adjust the "description": Minimum time to run old marking or old cleanup (C&F could be considered cleanup - or just say C&F)...

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Marked as reviewed by kdnilsen (Committer).

PR Review: https://git.openjdk.org/shenandoah/pull/526#pullrequestreview-2390913091
PR Review Comment: https://git.openjdk.org/shenandoah/pull/526#discussion_r1814048346