On Tue 23-04-19 08:44:05, Shakeel Butt wrote:
> The commit 475d0487a2ad ("mm: memcontrol: use per-cpu stocks for socket
> memory uncharging") added refill_stock() for skmem uncharging path to
> optimize workloads having high network traffic. Do the same for the kmem
> uncharging as well. Though we can bypass the refill for the offlined
> memcgs but it may impact the performance of network traffic for the
> sockets used by other cgroups.While the change makes sense, I would really like to see what kind of effect on performance does it really have. Do you have any specific workload that benefits from it? Thanks! > Signed-off-by: Shakeel Butt <shake...@google.com> > Cc: Roman Gushchin <g...@fb.com> > Cc: Johannes Weiner <han...@cmpxchg.org> > Cc: Michal Hocko <mho...@suse.com> > Cc: Vladimir Davydov <vdavydov....@gmail.com> > Cc: Andrew Morton <a...@linux-foundation.org> > --- > > Changelog since v1: > - No need to bypass offline memcgs in the refill. > > mm/memcontrol.c | 6 +----- > 1 file changed, 1 insertion(+), 5 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 2535e54e7989..2713b45ec3f0 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -2768,17 +2768,13 @@ void __memcg_kmem_uncharge(struct page *page, int > order) > if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) > page_counter_uncharge(&memcg->kmem, nr_pages); > > - page_counter_uncharge(&memcg->memory, nr_pages); > - if (do_memsw_account()) > - page_counter_uncharge(&memcg->memsw, nr_pages); > - > page->mem_cgroup = NULL; > > /* slab pages do not have PageKmemcg flag set */ > if (PageKmemcg(page)) > __ClearPageKmemcg(page); > > - css_put_many(&memcg->css, nr_pages); > + refill_stock(memcg, nr_pages); > } > #endif /* CONFIG_MEMCG_KMEM */ > > -- > 2.21.0.593.g511ec345e18-goog > -- Michal Hocko SUSE Labs
