On Mon, Jan 31, 2022 at 02:23:07PM -0500, Waiman Long wrote: > It was found that a number of offlined memcgs were not freed because > they were pinned by some charged pages that were present. Even "echo > 1 > /proc/sys/vm/drop_caches" wasn't able to free those pages. These > offlined but not freed memcgs tend to increase in number over time with > the side effect that percpu memory consumption as shown in /proc/meminfo > also increases over time. > > In order to find out more information about those pages that pin > offlined memcgs, the page_owner feature is extended to print memory > cgroup information especially whether the cgroup is offlined or not. > > Signed-off-by: Waiman Long <longman@xxxxxxxxxx> > Acked-by: David Rientjes <rientjes@xxxxxxxxxx> Acked-by: Roman Gushchin <guro@xxxxxx> Thanks!