From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with ESMTP id 777558D0039 for ; Mon, 7 Mar 2011 22:12:41 -0500 (EST) Received: from m1.gw.fujitsu.co.jp (unknown [10.0.50.71]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id AE9BA3EE0BD for ; Tue, 8 Mar 2011 12:12:37 +0900 (JST) Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 9507E45DE5C for ; Tue, 8 Mar 2011 12:12:37 +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 7E49945DE56 for ; Tue, 8 Mar 2011 12:12:37 +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 6C7FAE38003 for ; Tue, 8 Mar 2011 12:12:37 +0900 (JST) Received: from m106.s.css.fujitsu.com (m106.s.css.fujitsu.com [10.240.81.146]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 348511DB8047 for ; Tue, 8 Mar 2011 12:12:37 +0900 (JST) Date: Tue, 8 Mar 2011 12:06:17 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [patch] memcg: add oom killer delay Message-Id: <20110308120617.4039506a.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20110307171853.c31ec416.akpm@linux-foundation.org> References: <20110223150850.8b52f244.akpm@linux-foundation.org> <20110303135223.0a415e69.akpm@linux-foundation.org> <20110307162912.2d8c70c1.akpm@linux-foundation.org> <20110307165119.436f5d21.akpm@linux-foundation.org> <20110307171853.c31ec416.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: David Rientjes , Balbir Singh , Daisuke Nishimura , linux-mm@kvack.org On Mon, 7 Mar 2011 17:18:53 -0800 Andrew Morton wrote: > On Mon, 7 Mar 2011 17:02:36 -0800 (PST) > David Rientjes wrote: > > Keep in mind that for oom situations we give the killed > > task access to memory reserves below the min watermark with TIF_MEMDIE so > > that they can allocate memory to exit as quickly as possible (either to > > handle the SIGKILL or within the exit path). That's because we can't > > guarantee anything within an oom system, cpuset, mempolicy, or memcg is > > ever responsive without it. (And, the side effect of it and its threads > > exiting is the freeing of memory which allows everything else to once > > again be responsive.) > > > > > That this is the only situation you've observed in which the > > > userspace oom-handler is "unresponsive"? > > > > > > > Personally, yes, but I could imagine other users could get caught if their > > userspace oom handler requires taking locks (such as mmap_sem) by reading > > within procfs that a thread within an oom memcg already holds. > > If activity in one memcg cause a lockup of processes in a separate > memcg then that's a containment violation and we should fix it. > I hope dirty_ratio + async I/O controller will can be a help.. cpu controller is an only help for now (for limiting time for vmscan) I'm not sure what we need other than above for now. > One could argue that peering into a separate memcg's procfs files was > already a containment violation, but from a practical point of view we > definitely do want processes in a separate memcg to be able to > passively observe activity in another without stepping on lindmines. > It's namespace job, I think. 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