Re: [patch -mm v2 2/3] mm, memcg: replace cgroup aware oom killer mount option with tunable

Tejun Heo
2018-01-29T19:11:39Z

Hello, Michal.

On Mon, Jan 29, 2018 at 11:46:57AM +0100, Michal Hocko wrote:
> @@ -1292,7 +1292,11 @@ the memory controller considers only cgroups belonging to the sub-tree
> of the OOM'ing cgroup.
>
> The root cgroup is treated as a leaf memory cgroup, so it's compared
> -with other leaf memory cgroups and cgroups with oom_group option set.
> +with other leaf memory cgroups and cgroups with oom_group option
> +set. Due to internal implementation restrictions the size of the root
> +cgroup is a cumulative sum of oom_badness of all its tasks (in other
> +words oom_score_adj of each task is obeyed). This might change in the
> +future.

Thanks, we can definitely use more documentation. However, it's a bit
difficult to follow. Maybe expand it to a separate paragraph on the
current behavior with a clear warning that the default OOM heuristics
is subject to changes?

Thanks.

--
tejun