On Tue, Jun 1, 2021 at 10:45 PM Chris Down <chris@xxxxxxxxxxxxxx> wrote: > > yulei zhang writes: > >Yep, dynamically adjust the memory.high limits can ease the memory pressure > >and postpone the global reclaim, but it can easily trigger the oom in > >the cgroups, > > To go further on Shakeel's point, which I agree with, memory.high should > _never_ result in memcg OOM. Even if the limit is breached dramatically, we > don't OOM the cgroup. If you have a demonstration of memory.high resulting in > cgroup-level OOM kills in recent kernels, then that needs to be provided. :-) You are right, I mistook it for max. Shakeel means the throttling during context switch which uses memory.high as threshold to calculate the sleep time. Currently it only applies to cgroupv2. In this patchset we explore another idea to throttle the memory usage, which rely on setting an average allocation speed in memcg. We hope to suppress the memory usage in low priority cgroups when it reaches the system watermark and still keep the activities alive.