On Wed, 18 May 2011 08:49:19 +0900
KAMEZAWA Hiroyuki <
kamezawa.hiroyu@jp.fujitsu.com> wrote:
> On Mon, 16 May 2011 17:18:20 -0700
> Andrew Morton <
akpm@linux-foundation.org> wrote:
>
> > On Mon, 16 May 2011 17:05:02 -0700
> > Ying Han <
yinghan@google.com> wrote:
> >
> > > On Mon, May 16, 2011 at 4:15 PM, Johannes Weiner <
hannes@cmpxchg.org> wrote:
> > >
> > > > On Mon, May 16, 2011 at 03:00:30PM -0700, Ying Han wrote:
> > > > > This fixes the typo in the memory.stat including the following two
> > > > > stats:
> > > > >
> > > > > $ cat /dev/cgroup/memory/A/memory.stat
> > > > > total_soft_steal 0
> > > > > total_soft_scan 0
> > > > >
> > > > > And change it to:
> > > > >
> > > > > $ cat /dev/cgroup/memory/A/memory.stat
> > > > > total_soft_kswapd_steal 0
> > > > > total_soft_kswapd_scan 0
> > > > >
> > > > > Signed-off-by: Ying Han <
yinghan@google.com>
> > > >
> > > > I am currently proposing and working on a scheme that makes the soft
> > > > limit not only a factor for global memory pressure, but for
> > > > hierarchical reclaim in general, to prefer child memcgs during reclaim
> > > > that are in excess of their soft limit.
> > > >
> > > > Because this means prioritizing memcgs over one another, rather than
> > > > having explicit soft limit reclaim runs, there is no natural counter
> > > > for pages reclaimed due to the soft limit anymore.
> > > >
> > > > Thus, for the patch that introduces this counter:
> > > >
> > > > Nacked-by: Johannes Weiner <
hannes@cmpxchg.org>
> > > >
> > >
> > > This patch is fixing a typo of the stats being integrated into mmotm. Does
> > > it make sense to fix the
> > > existing stats first while we are discussing other approaches?
> > >
> >
> > It would be quite bad to add new userspace-visible stats and to then
> > take them away again.
> >
> yes.
>
> > But given that memcg-add-stats-to-monitor-soft_limit-reclaim.patch is
> > queued for 2.6.39-rc1, we could proceed with that plan and then make
> > sure that Johannes's changes are merged either prior to 2.6.40 or
> > they are never merged at all.
> >
> > Or we could just leave out the stats until we're sure. Not having them
> > for a while is not as bad as adding them and then removing them.
> >
>
> I agree. I'm okay with removing them for a while. Johannes and Ying, could you
> make a concensus ? IMHO, Johannes' work for making soft-limit co-operative with
> hirerachical reclaim makes sense and agree to leave counter name as it is.
>