From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id E54BE6B0047 for ; Tue, 31 Mar 2009 02:48:43 -0400 (EDT) Received: from d23relay02.au.ibm.com (d23relay02.au.ibm.com [202.81.31.244]) by e23smtp04.au.ibm.com (8.13.1/8.13.1) with ESMTP id n2V6lQjh029233 for ; Tue, 31 Mar 2009 17:47:26 +1100 Received: from d23av04.au.ibm.com (d23av04.au.ibm.com [9.190.235.139]) by d23relay02.au.ibm.com (8.13.8/8.13.8/NCO v9.2) with ESMTP id n2V6nPMu1134662 for ; Tue, 31 Mar 2009 17:49:25 +1100 Received: from d23av04.au.ibm.com (loopback [127.0.0.1]) by d23av04.au.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id n2V6nPZm024056 for ; Tue, 31 Mar 2009 17:49:25 +1100 Date: Tue, 31 Mar 2009 12:19:02 +0530 From: Balbir Singh Subject: Re: [RFC][PATCH] memcg soft limit (yet another new design) v1 Message-ID: <20090331064901.GK16497@balbir.in.ibm.com> Reply-To: balbir@linux.vnet.ibm.com References: <20090327135933.789729cb.kamezawa.hiroyu@jp.fujitsu.com> <20090328181100.GB26686@balbir.in.ibm.com> <20090328182747.GA8339@balbir.in.ibm.com> <20090331085538.2aaa5e2b.kamezawa.hiroyu@jp.fujitsu.com> <20090331050055.GF16497@balbir.in.ibm.com> <20090331140502.813993cc.kamezawa.hiroyu@jp.fujitsu.com> <20090331061010.GJ16497@balbir.in.ibm.com> <20090331152843.e1db942b.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20090331152843.e1db942b.kamezawa.hiroyu@jp.fujitsu.com> Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki Cc: "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "kosaki.motohiro@jp.fujitsu.com" , "nishimura@mxp.nes.nec.co.jp" List-ID: * KAMEZAWA Hiroyuki [2009-03-31 15:28:43]: > On Tue, 31 Mar 2009 11:40:10 +0530 > Balbir Singh wrote: > > > > > Swapout for A? For A it is expected, but for B it is not. How many > > > > nodes do you have on your machine? Any fake numa nodes? > > > > > > > Of course, from B. > > > > > > > I asked because I see A have a swapout of 350 MB, which is expected > > since it is way over its soft limit. > > > gcc doesn't use so much RSS..ld ? Yes, the ld step consumes a lot of memory, depending on file size and number of parallel tasks, memory consumption does go up. > > > > Nothing special boot options. My test was on VMware 2cpus/1.6GB memory. > > > > > > I wonder why swapout can be 0 on your test. Do you add some extra hooks to > > > kswapd ? > > > > > > > Nope.. no special hooks to kswapd. B never enters the RB-Tree and thus > > never hits the memcg soft limit reclaim path. kswapd can reclaim from > > it, but it grows back quickly. > Why grows back ? tasks in B sleeps ? Since B continuously consumes memory > > > At some point, memcg soft limit reclaim > > hits A and reclaims memory from it, allowing B to run without any > > problems. I am talking about the state at the end of the experiment. > > > Considering LRU rotation (ACTIVE->INACTIVE), pages in group B never goes back > to ACTIVE list and can be the first candidates for swap-out via kswapd. > > Hmm....kswapd doesn't work at all ? > > (or 1700MB was too much.) > No 1700MB is not too much, since we reclaim from A towards the end when ld runs. I need to investigate more and look at the watermarks, may be soft limit reclaim reclaims enough and/or the watermarks are not very high. I use fake NUMA nodes as well. > Thanks, > -Kame > > -- Balbir -- 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