From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id 4E8F86B0044 for ; Tue, 3 Nov 2009 22:22:39 -0500 (EST) Received: from m6.gw.fujitsu.co.jp ([10.0.50.76]) by fgwmail5.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id nA43Ma26013907 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Wed, 4 Nov 2009 12:22:36 +0900 Received: from smail (m6 [127.0.0.1]) by outgoing.m6.gw.fujitsu.co.jp (Postfix) with ESMTP id 49D3745DE50 for ; Wed, 4 Nov 2009 12:22:36 +0900 (JST) Received: from s6.gw.fujitsu.co.jp (s6.gw.fujitsu.co.jp [10.0.50.96]) by m6.gw.fujitsu.co.jp (Postfix) with ESMTP id 11BD845DE58 for ; Wed, 4 Nov 2009 12:22:36 +0900 (JST) Received: from s6.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s6.gw.fujitsu.co.jp (Postfix) with ESMTP id A70071DB8041 for ; Wed, 4 Nov 2009 12:22:35 +0900 (JST) Received: from m108.s.css.fujitsu.com (m108.s.css.fujitsu.com [10.249.87.108]) by s6.gw.fujitsu.co.jp (Postfix) with ESMTP id F3FF7E38005 for ; Wed, 4 Nov 2009 12:22:34 +0900 (JST) Date: Wed, 4 Nov 2009 12:19:52 +0900 From: KAMEZAWA Hiroyuki Subject: Re: Memory overcommit Message-Id: <20091104121952.07ea695a.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: References: <20091028150536.674abe68.kamezawa.hiroyu@jp.fujitsu.com> <20091028152015.3d383cd6.kamezawa.hiroyu@jp.fujitsu.com> <4AE97861.1070902@gmail.com> <20091030084836.5428e085.kamezawa.hiroyu@jp.fujitsu.com> <20091030183638.1125c987.kamezawa.hiroyu@jp.fujitsu.com> <20091104095021.5532e913.kamezawa.hiroyu@jp.fujitsu.com> <20091104111703.b46ae72b.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: David Rientjes Cc: vedran.furac@gmail.com, Hugh Dickins , linux-mm@kvack.org, linux-kernel@vger.kernel.org, KOSAKI Motohiro , minchan.kim@gmail.com, Andrew Morton , Andrea Arcangeli List-ID: On Tue, 3 Nov 2009 19:10:34 -0800 (PST) David Rientjes wrote: > On Wed, 4 Nov 2009, KAMEZAWA Hiroyuki wrote: > > > My point and your point are differnt. > > > > 1. All my concern is "baseline for heuristics" > > 2. All your concern is "baseline for knob, as oom_adj" > > > > ok ? For selecting victim by the kernel, dynamic value is much more useful. > > Current behavior of "Random kill" and "Kill multiple processes" are too bad. > > Considering oom-killer is for what, I think "1" is more important. > > > > But I know what you want, so, I offers new knob which is not affected by RSS > > as I wrote in previous mail. > > > > Off-topic: > > As memcg is growing better, using OOM-Killer for resource control should be > > ended, I think. Maybe Fake-NUMA+cpuset is working well for google system, > > but plz consider to use memcg. > > > > I understand what you're trying to do, and I agree with it for most > desktop systems. However, I think that admins should have a very strong > influence in what tasks the oom killer kills. It doesn't really matter if > it's via oom_adj or not, and its debatable whether an adjustment on a > static heuristic score is in our best interest in the first place. But we > must have an alternative so that our control over oom killing isn't lost. > I'll not go too quickly, so, let's discuss and rewrite patches more, later. I'll parepare new version in the next week. For this week, I'll post swap accounting and improve fork-bomb detector. > I'd also like to open another topic for discussion if you're proposing > such sweeping changes: at what point do we allow ~__GFP_NOFAIL allocations > to fail even if order < PAGE_ALLOC_COSTLY_ORDER and defer killing > anything? We both agreed that it's not always in the best interest to > kill a task so that an allocation can succeed, so we need to define some > criteria to simply fail the allocation instead. > Yes, I think allocation itself (> order=0) should fail more before we finally invoke OOM. It tends to be soft-landing rather than oom-killer. 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/ . Don't email: email@kvack.org