On Wed, 3 Jul 2019, Waiman Long wrote: > On 7/3/19 2:56 AM, Michal Hocko wrote: > > On Tue 02-07-19 14:37:30, Waiman Long wrote: > >> Currently, a value of '1" is written to /sys/kernel/slab/<slab>/shrink > >> file to shrink the slab by flushing all the per-cpu slabs and free > >> slabs in partial lists. This applies only to the root caches, though. > >> > >> Extends this capability by shrinking all the child memcg caches and > >> the root cache when a value of '2' is written to the shrink sysfs file. > > Why do we need a new value for this functionality? I would tend to think > > that skipping memcg caches is a bug/incomplete implementation. Or is it > > a deliberate decision to cover root caches only? > > It is just that I don't want to change the existing behavior of the > current code. It will definitely take longer to shrink both the root > cache and the memcg caches. If we all agree that the only sensible > operation is to shrink root cache and the memcg caches together. I am > fine just adding memcg shrink without changing the sysfs interface > definition and be done with it.
I think its best and consistent behavior to shrink all memcg caches with the root cache. This looks like an oversight and thus a bugfix.
