lkml.org 
[lkml]   [2012]   [Mar]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH -V4 04/10] memcg: Add HugeTLB extension
On Wed 28-03-12 23:07:14, Aneesh Kumar K.V wrote:
> Michal Hocko <mhocko@suse.cz> writes:
>
> > On Fri 16-03-12 23:09:24, Aneesh Kumar K.V wrote:
> > [...]
> >> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> >> index 6728a7a..4b36c5e 100644
> >> --- a/mm/memcontrol.c
> >> +++ b/mm/memcontrol.c
> > [...]
> >> @@ -4887,6 +5013,7 @@ err_cleanup:
> >> static struct cgroup_subsys_state * __ref
> >> mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
> >> {
> >> + int idx;
> >> struct mem_cgroup *memcg, *parent;
> >> long error = -ENOMEM;
> >> int node;
> >> @@ -4929,9 +5056,14 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
> >> * mem_cgroup(see mem_cgroup_put).
> >> */
> >> mem_cgroup_get(parent);
> >> + for (idx = 0; idx < HUGE_MAX_HSTATE; idx++)
> >> + res_counter_init(&memcg->hugepage[idx],
> >> + &parent->hugepage[idx]);
> >
> > Hmm, I do not think we want to make groups deeper in the hierarchy
> > unlimited as we cannot reclaim. Shouldn't we copy the limit from the parent?
> > Still not ideal but slightly more expected behavior IMO.
>
> But we should be limiting the child group based on parent's limit only
> when hierarchy is set right ?

Yes. Everything else should be unlimited by default.

>
> >
> > The hierarchy setups are still interesting and the limitations should be
> > described in the documentation...
> >
>
> It should behave similar to memcg. ie, if hierarchy is set, then we limit
> using MIN(parent's limit, child's limit). May be I am missing some of
> the details of memcg use_hierarchy config. My goal was to keep it
> similar to memcg. Can you explain why do you think the patch would
> make it any different ?

Yes, the patch tries to be consistent with the memcg limits. That is OK
and I have no objections for that. It is just that consequences are
different. The hugetlb limit is really hard...

>
> -aneesh
>
> --
> To unsubscribe from this list: send the line "unsubscribe cgroups" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html

--
Michal Hocko
SUSE Labs
SUSE LINUX s.r.o.
Lihovarska 1060/12
190 00 Praha 9
Czech Republic


\
 
 \ /
  Last update: 2012-03-29 09:59    [W:0.081 / U:0.036 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site