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 ESMTP id 020556B0044 for ; Tue, 3 Nov 2009 15:50:04 -0500 (EST) Received: from spaceape24.eur.corp.google.com (spaceape24.eur.corp.google.com [172.28.16.76]) by smtp-out.google.com with ESMTP id nA3Ko0Fv002052 for ; Tue, 3 Nov 2009 12:50:00 -0800 Received: from pxi31 (pxi31.prod.google.com [10.243.27.31]) by spaceape24.eur.corp.google.com with ESMTP id nA3KnJ59018784 for ; Tue, 3 Nov 2009 12:49:57 -0800 Received: by pxi31 with SMTP id 31so314620pxi.9 for ; Tue, 03 Nov 2009 12:49:56 -0800 (PST) Date: Tue, 3 Nov 2009 12:49:52 -0800 (PST) From: David Rientjes Subject: Re: Memory overcommit In-Reply-To: <20091030183638.1125c987.kamezawa.hiroyu@jp.fujitsu.com> Message-ID: References: <4AE78B8F.9050201@gmail.com> <4AE792B8.5020806@gmail.com> <20091028135519.805c4789.kamezawa.hiroyu@jp.fujitsu.com> <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> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki 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 Fri, 30 Oct 2009, KAMEZAWA Hiroyuki wrote: > > > - The kernel can't know the program is bad or not. just guess it. > > > > Totally irrelevant, given your fourth point about /proc/pid/oom_adj. We > > can tell the kernel what we'd like the oom killer behavior should be if > > the situation arises. > > > > My point is that the server cannot distinguish memory leak from intentional > memory usage. No other than that. > That's a different point. Today, we can influence the badness score of any user thread to prioritize oom killing from userspace and that can be done regardless of whether there's a memory leaker, a fork bomber, etc. The priority based oom killing is important to production scenarios and cannot be replaced by a heuristic that works everytime if it cannot be influenced by userspace. A spike in memory consumption when a process is initially forked would be defined as a memory leaker in your quiet_time model. > In this summer, at lunch with a daily linux user, I was said > "you, enterprise guys, don't consider desktop or laptop problem at all." > yes, I use only servers. My customer uses server, too. My first priority > is always on server users. > But, for this time, I wrote reply to Vedran and try to fix desktop problem. > Even if current logic works well for servers, "KDE/GNOME is killed" problem > seems to be serious. And this may be a problem for EMBEDED people, I guess. > You argued before that the problem wasn't specific to X (after I said you could protect it very trivially with /proc/pid/oom_adj set to OOM_DISABLE), but that's now your reasoning for rewriting the oom killer heuristics? > I can say the same thing to total_vm size. total_vm size doesn't include any > good information for oom situation. And tweaking based on that not-useful > parameter will make things worse. > Tweaking on the heuristic will probably make it more convoluted and overall worse, I agree. But it's a more stable baseline than rss from which we can set oom killing priorities from userspace. -- 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