Re: çå: çå: [PATCH] mm/memcontrol.c: speed up to force empty a memory cgroup

From: David Rientjes
Date: Tue Mar 20 2018 - 18:45:40 EST


On Wed, 21 Mar 2018, Andrey Ryabinin wrote:

> > Is SWAP_CLUSTER_MAX the best answer if I'm lowering the limit by 1GB?
> >
>
> Absolutely not. I completely on your side here.
> I've tried to fix this recently - http://lkml.kernel.org/r/20180119132544.19569-2-aryabinin@xxxxxxxxxxxxx
> I guess that Andrew decided to not take my patch, because Michal wasn't
> happy about it (see mail archives if you want more details).
>

I unfortunately didn't see this patch in January, it seems very similar to
what I was suggesting in this thread. You do a page_counter_read()
directly in mem_cgroup_resize_limit() where my suggestion was to have
page_counter_limit() return the difference, but there's nothing
significantly different about what you proposed and what I suggested.

Perhaps the patch would be better off as a compromise between what you, I,
and Li RongQing have proposed/suggested: have page_counter_limit() return
the difference, and clamp it to some value proportional to the new limit.