Re: [PATCH] mm: memcontrol: fix occasional OOMs due to proportional memory.low reclaim
From: Michal Koutný <mkoutny@suse.com>
Date: 2021-08-23 16:09:43
Also in:
cgroups, lkml
Hello (and sorry for a belated reply). On Tue, Aug 17, 2021 at 02:05:06PM -0400, Johannes Weiner [off-list ref] wrote:
quoted hunk ↗ jump to hunk
@@ -2576,6 +2578,15 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc,[...] + /* memory.low scaling, make sure we retry before OOM */ + if (!sc->memcg_low_reclaim && low > min) { + protection = low; + sc->memcg_low_skipped = 1;
IIUC, this won't result in memory.events:low increment although the effect is similar (breaching (partial) memory.low protection) and signal to the user is comparable (overcommited memory.low). Admittedly, this patch's behavior adheres to the current documentation (Documentation/admin-guide/cgroup-v2.rst):
The number of times the cgroup is reclaimed due to high memory pressure even though its usage is under the low boundary,
however, that definition might not be what the useful indicator would be now. Is it worth including these partial breaches into memory.events:low? Regards, Michal