Re: [PATCH] mm: vmscan: abort proactive reclaim early when freezing
From: Shakeel Butt
Date: Tue Jul 07 2026 - 15:49:11 EST
On Mon, Jul 06, 2026 at 08:12:18AM +0000, Richard Chang wrote:
> Proactive reclaim (via memory.reclaim or node reclaim) checks for pending
> signals in its outer loop in user_proactive_reclaim(). However, the inner
> reclaim loops—scanning cgroups in shrink_many() and evicting folios in
> try_to_shrink_lruvec() can run for a long time before returning to the
> outer loop, especially on systems with many cgroups or large memory sizes.
>
> This latency in responding to signals can block the freezer (both cgroup
> freezer and system suspend), leading to freezer timeouts. This issue was
> specifically observed on Android when attempting to freeze background
> cgroups while proactive reclaim was active.
>
Can you please explain how freezing operation was delayed due to proactive
reclaim?