On Wed, 20 Apr 2011 23:59:52 -0700

Ying Han <yinghan@google.com> wrote:

> On Wed, Apr 20, 2011 at 11:38 PM, KAMEZAWA Hiroyuki <
> kamezawa.hiroyu@jp.fujitsu.com> wrote:
>
> > On Wed, 20 Apr 2011 23:11:42 -0700
> > Ying Han <yinghan@google.com> wrote:
> >
> > > On Wed, Apr 20, 2011 at 8:48 PM, KAMEZAWA Hiroyuki <
> > > kamezawa.hiroyu@jp.fujitsu.com> wrote:

> n general, memcg-kswapd can reduce memory down to high watermak only when
> > the system is not busy. So, this logic tries to remove more memory from busy
> > cgroup to reduce 'hit limit'.
> >
>
> So, the "busy cgroup" here means the memcg has higher (usage - low)?
>

 high < usage < low < limit

Yes, if background reclaim wins, usage - high decreases.
If tasks on cgroup uses more memory than reclaim, usage - high increases even
if background reclaim runs. So, if usage-high is large, cgroup is busy.

Thanks,
-Kame