CC Andrew - can you route these through the -mm tree please? On Thu, Jul 27, 2017 at 02:04:27PM +0100, Roman Gushchin wrote: > A removed memory cgroup with a defined memory.low and some belonging > pagecache has very low chances to be freed. > > If a cgroup has been removed, there is likely no memory pressure inside > the cgroup, and the pagecache is protected from the external pressure > by the defined low limit. The cgroup will be freed only after > the reclaim of all belonging pages. And it will not happen until > there are any reclaimable memory in the system. That means, > there is a good chance, that a cold pagecache will reside > in the memory for an undefined amount of time, wasting > system resources. > > This problem was fixed earlier by commit fa06235b8eb0 > ("cgroup: reset css on destruction"), but it's not a best way > to do it, as we can't really reset all limits/counters during > cgroup offlining. > > Signed-off-by: Roman Gushchin <guro@xxxxxx> > Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx> > Cc: Tejun Heo <tj@xxxxxxxxxx> > Cc: Johannes Weiner <hannes@xxxxxxxxxxx> > Cc: Michal Hocko <mhocko@xxxxxxxxxx> > Cc: kernel-team@xxxxxx > Cc: cgroups@xxxxxxxxxxxxxxx > Cc: linux-mm@xxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>