From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta8.messagelabs.com (mail6.bemta8.messagelabs.com [216.82.243.55]) by kanga.kvack.org (Postfix) with ESMTP id 2D452900138 for ; Wed, 17 Aug 2011 19:59:57 -0400 (EDT) Received: from m1.gw.fujitsu.co.jp (unknown [10.0.50.71]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id C97FD3EE0AE for ; Thu, 18 Aug 2011 08:59:53 +0900 (JST) Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id AB25345DE5A for ; Thu, 18 Aug 2011 08:59:53 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 82DA545DE58 for ; Thu, 18 Aug 2011 08:59:53 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 776A11DB804B for ; Thu, 18 Aug 2011 08:59:53 +0900 (JST) Received: from m105.s.css.fujitsu.com (m105.s.css.fujitsu.com [10.240.81.145]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 425A81DB8051 for ; Thu, 18 Aug 2011 08:59:53 +0900 (JST) Date: Thu, 18 Aug 2011 08:52:33 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH v5 2/6] memcg: stop vmscan when enough done. Message-Id: <20110818085233.69dbf23b.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20110817113550.GA7482@tiehlicka.suse.cz> References: <20110809190450.16d7f845.kamezawa.hiroyu@jp.fujitsu.com> <20110809190933.d965888b.kamezawa.hiroyu@jp.fujitsu.com> <20110810141425.GC15007@tiehlicka.suse.cz> <20110811085252.b29081f1.kamezawa.hiroyu@jp.fujitsu.com> <20110811145055.GN8023@tiehlicka.suse.cz> <20110817095405.ee3dcd74.kamezawa.hiroyu@jp.fujitsu.com> <20110817113550.GA7482@tiehlicka.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "akpm@linux-foundation.org" , "hannes@cmpxchg.org" , "nishimura@mxp.nes.nec.co.jp" On Wed, 17 Aug 2011 13:35:50 +0200 Michal Hocko wrote: > On Wed 17-08-11 09:54:05, KAMEZAWA Hiroyuki wrote: > > On Thu, 11 Aug 2011 16:50:55 +0200 > > Michal Hocko wrote: > > > > > What about this (just compile tested)? > > > --- > > > From: Michal Hocko > > > Subject: memcg: add nr_pages argument for hierarchical reclaim > > > > > > Now that we are doing memcg direct reclaim limited to nr_to_reclaim > > > pages (introduced by "memcg: stop vmscan when enough done.") we have to > > > be more careful. Currently we are using SWAP_CLUSTER_MAX which is OK for > > > most callers but it might cause failures for limit resize or force_empty > > > code paths on big NUMA machines. > > > > > > Previously we might have reclaimed up to nr_nodes * SWAP_CLUSTER_MAX > > > while now we have it at SWAP_CLUSTER_MAX. Both resize and force_empty rely > > > on reclaiming a certain amount of pages and retrying if their condition is > > > still not met. > > > > > > Let's add nr_pages argument to mem_cgroup_hierarchical_reclaim which will > > > push it further to try_to_free_mem_cgroup_pages. We still fall back to > > > SWAP_CLUSTER_MAX for small requests so the standard code (hot) paths are not > > > affected by this. > > > > > > Open questions: > > > - Should we care about soft limit as well? Currently I am using excess > > > number of pages for the parameter so it can replace direct query for > > > the value in mem_cgroup_hierarchical_reclaim but should we push it to > > > mem_cgroup_shrink_node_zone? > > > I do not think so because we should try to reclaim from more groups in the > > > hierarchy and also it doesn't get to shrink_zones which has been modified > > > by the previous patch. > > > > > > > > > - mem_cgroup_force_empty asks for reclaiming all pages. I guess it should be > > > OK but will have to think about it some more. > > > > force_empty/rmdir() is allowed to be stopped by Ctrl-C. I think passing res->usage > > is overkilling. > > So, how many pages should be reclaimed then? > How about (1 << (MAX_ORDER-1))/loop ? Thanks, -Kame -- 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