On Wed 25-01-12 15:07:47, Ying Han wrote: > On Tue, Jan 24, 2012 at 12:43 AM, Michal Hocko <mhocko@xxxxxxx> wrote: > > On Mon 23-01-12 14:05:33, Ying Han wrote: [...] > >> Just want to make sure I understand it, even we make the lock > >> per-memcg, there is still a false sharing of pc within one memcg. > > > > Yes that is true. I have missed that we might fault in several pages at > > once but this would happen only during task move, right? And that is not > > a hot path anyway. Or? > > I was thinking of page-statistics update which is hot path. If the > moving task and non-moving task share the same per-memcg lock, any > page-statistic update from the non-moving task will be blocked? Sorry > If i missed something here :) OK, I got your point, finally. I guess there is a plan to reduce the effect by array of locks. -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>