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charset=us-ascii Content-Disposition: inline In-Reply-To: <20200422132632.GG30312@dhcp22.suse.cz> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Apr 22, 2020 at 03:26:32PM +0200, Michal Hocko wrote: > That being said I believe our discussion is missing an important part. > There is no description of the swap.high semantic. What can user expect > when using it? Good point, we should include that in cgroup-v2.rst. How about this? diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index bcc80269bb6a..49e8733a9d8a 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -1370,6 +1370,17 @@ PAGE_SIZE multiple when read back. The total amount of swap currently being used by the cgroup and its descendants. + memory.swap.high + A read-write single value file which exists on non-root + cgroups. The default is "max". + + Swap usage throttle limit. If a cgroup's swap usage exceeds + this limit, allocations inside the cgroup will be throttled. + + This slows down expansion of the group's memory footprint as + it runs out of assigned swap space. Compare to memory.swap.max, + which stops swapping abruptly and can provoke kernel OOM kills. + memory.swap.max A read-write single value file which exists on non-root cgroups. The default is "max".