From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta12.messagelabs.com (mail6.bemta12.messagelabs.com [216.82.250.247]) by kanga.kvack.org (Postfix) with ESMTP id 52D3A6B00FC for ; Tue, 28 Jun 2011 04:53:38 -0400 (EDT) Date: Tue, 28 Jun 2011 10:53:36 +0200 From: Michal Hocko Subject: Re: [patch 14/22] memcg: fix direct softlimit reclaim to be called in limit path Message-ID: <20110628085335.GA17961@tiehlicka.suse.cz> References: <201106272318.p5RNICJW001465@imap1.linux-foundation.org> <20110628080847.GA16518@tiehlicka.suse.cz> <20110628170649.87043e05.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110628170649.87043e05.kamezawa.hiroyu@jp.fujitsu.com> Sender: owner-linux-mm@kvack.org List-ID: To: KAMEZAWA Hiroyuki Cc: Andrew Morton , torvalds@linux-foundation.org, nishimura@mxp.nes.nec.co.jp, yinghan@google.com, linux-mm@kvack.org, LKML On Tue 28-06-11 17:06:49, KAMEZAWA Hiroyuki wrote: > On Tue, 28 Jun 2011 10:08:47 +0200 > Michal Hocko wrote: > > > I am sorry, that I am answering that late but I didn't get to this > > sooner. > > > > On Mon 27-06-11 16:18:12, Andrew Morton wrote: > > > From: KAMEZAWA Hiroyuki > > > > > > commit d149e3b ("memcg: add the soft_limit reclaim in global direct > > > reclaim") adds a softlimit hook to shrink_zones(). By this, soft limit is > > > called as > > > > > > try_to_free_pages() > > > do_try_to_free_pages() > > > shrink_zones() > > > mem_cgroup_soft_limit_reclaim() > > > > > > Then, direct reclaim is memcg softlimit hint aware, now. > > > > > > But, the memory cgroup's "limit" path can call softlimit shrinker. > > > > > > try_to_free_mem_cgroup_pages() > > > do_try_to_free_pages() > > > shrink_zones() > > > mem_cgroup_soft_limit_reclaim() > > > > > > This will cause a global reclaim when a memcg hits limit. > > > > Sorry, I do not get it. How does it cause the global reclaim? Did you > > mean soft reclaim? > > > > yes. soft reclaim does global reclaim (in some means). But calling it global reclaim is rather confusing because in both paths we have sc.mem_cgroup set to non-NULL which is evaluated as !scanning_global_lru(sc). Anyway, this is not that important, I just wanted to be sure what you meant by that comment. -- 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@kvack.org. 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: email@kvack.org