[Devel] Re: [PATCH v2 02/13] memcg: Kernel memory accounting infrastructure.

[KAMEZAWA Hiroyuki]

On Sun, 11 Mar 2012 12:12:04 +0400
Glauber Costa <glommer at parallels.com> wrote:

> On 03/10/2012 12:39 AM, Suleiman Souhlal wrote:
> > Enabled with CONFIG_CGROUP_MEM_RES_CTLR_KMEM.
> >
> > Adds the following files:
> >      - memory.kmem.independent_kmem_limit
> >      - memory.kmem.usage_in_bytes
> >      - memory.kmem.limit_in_bytes
> >
> > Signed-off-by: Suleiman Souhlal<suleiman at google.com>
> > ---
> >   mm/memcontrol.c |  136 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
> >   1 files changed, 135 insertions(+), 1 deletions(-)
> >
> > diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> > index 37ad2cb..e6fd558 100644
> > --- a/mm/memcontrol.c
> > +++ b/mm/memcontrol.c
> > @@ -220,6 +220,10 @@ enum memcg_flags {
> >   				 */
> >   	MEMCG_MEMSW_IS_MINIMUM,	/* Set when res.limit == memsw.limit */
> >   	MEMCG_OOM_KILL_DISABLE,	/* OOM-Killer disable */
> > +	MEMCG_INDEPENDENT_KMEM_LIMIT,	/*
> > +					 * kernel memory is not counted in
> > +					 * memory.usage_in_bytes
> > +					 */
> >   };


After looking codes, I think we need to think
whether independent_kmem_limit is good or not....

How about adding MEMCG_KMEM_ACCOUNT flag instead of this and use only
memcg->res/memcg->memsw rather than adding a new counter, memcg->kmem ?

if MEMCG_KMEM_ACCOUNT is set     -> slab is accoutned to mem->res/memsw.
if MEMCG_KMEM_ACCOUNT is not set -> slab is never accounted.

(I think On/Off switch is required..)

Thanks,
-Kame