From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id CEA716B0012 for ; Mon, 2 May 2011 18:53:56 -0400 (EDT) Received: from wpaz1.hot.corp.google.com (wpaz1.hot.corp.google.com [172.24.198.65]) by smtp-out.google.com with ESMTP id p42MrsIT015804 for ; Mon, 2 May 2011 15:53:54 -0700 Received: from ywa8 (ywa8.prod.google.com [10.192.1.8]) by wpaz1.hot.corp.google.com with ESMTP id p42MqtOQ015275 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for ; Mon, 2 May 2011 15:53:52 -0700 Received: by ywa8 with SMTP id 8so2167822ywa.9 for ; Mon, 02 May 2011 15:53:52 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1304366849.15370.27.camel@mulgrave.site> References: <1304366849.15370.27.camel@mulgrave.site> From: Paul Menage Date: Mon, 2 May 2011 15:53:31 -0700 Message-ID: Subject: Re: memcg: fix fatal livelock in kswapd Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org List-ID: To: James Bottomley , Balbir Singh , KAMEZAWA Hiroyuki , nishimura@mxp.nes.nec.co.jp Cc: Chris Mason , linux-fsdevel , linux-mm , linux-kernel , Li Zefan , containers@lists.linux-foundation.org [ Adding the memcg maintainers ] On Mon, May 2, 2011 at 1:07 PM, James Bottomley wrote: > The fatal livelock in kswapd, reported in this thread: > > http://marc.info/?t=3D130392066000001 > > Is mitigateable if we prevent the cgroups code being so aggressive in > its zone shrinking (by reducing it's default shrink from 0 [everything] > to DEF_PRIORITY [some things]). =A0This will have an obvious knock on > effect to cgroup accounting, but it's better than hanging systems. > > Signed-off-by: James Bottomley > > --- > > From 74b62fc417f07e1411d98181631e4e097c8e3e68 Mon Sep 17 00:00:00 2001 > From: James Bottomley > Date: Mon, 2 May 2011 14:56:29 -0500 > Subject: [PATCH] vmscan: move containers scan back to default priority > > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index f6b435c..46cde92 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -2173,8 +2173,12 @@ unsigned long mem_cgroup_shrink_node_zone(struct m= em_cgroup *mem, > =A0 =A0 =A0 =A0 * if we don't reclaim here, the shrink_zone from balance_= pgdat > =A0 =A0 =A0 =A0 * will pick up pages from other mem cgroup's as well. We = hack > =A0 =A0 =A0 =A0 * the priority and make it zero. > + =A0 =A0 =A0 =A0* > + =A0 =A0 =A0 =A0* FIXME: jejb: zero here was causing a livelock in the > + =A0 =A0 =A0 =A0* shrinker so changed to DEF_PRIORITY to fix this. Now n= eed to > + =A0 =A0 =A0 =A0* sort out cgroup accounting. > =A0 =A0 =A0 =A0 */ > - =A0 =A0 =A0 shrink_zone(0, zone, &sc); > + =A0 =A0 =A0 shrink_zone(DEF_PRIORITY, zone, &sc); > > =A0 =A0 =A0 =A0trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaime= d); > > > > -- 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