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 SMTP id 381146B00A3 for ; Mon, 18 Oct 2010 21:15:09 -0400 (EDT) Received: by gxk27 with SMTP id 27so978215gxk.14 for ; Mon, 18 Oct 2010 18:15:07 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20101019095144.A1B0.A69D9226@jp.fujitsu.com> References: <20101019093142.509d6947@notabene> <20101018154137.90f5325f.akpm@linux-foundation.org> <20101019095144.A1B0.A69D9226@jp.fujitsu.com> Date: Tue, 19 Oct 2010 10:15:06 +0900 Message-ID: Subject: Re: Deadlock possibly caused by too_many_isolated. From: Minchan Kim Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org To: KOSAKI Motohiro Cc: Andrew Morton , Neil Brown , Wu Fengguang , Rik van Riel , KAMEZAWA Hiroyuki , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "Li, Shaohua" List-ID: On Tue, Oct 19, 2010 at 9:57 AM, KOSAKI Motohiro wrote: >> > I think there are two bugs here. >> > The raid1 bug that Torsten mentions is certainly real (and has been ar= ound >> > for an embarrassingly long time). >> > The bug that I identified in too_many_isolated is also a real bug and = can be >> > triggered without md/raid1 in the mix. >> > So this is not a 'full fix' for every bug in the kernel :-), but it co= uld >> > well be a full fix for this particular bug. >> > >> >> Can we just delete the too_many_isolated() logic? =A0(Crappy comment >> describes what the code does but not why it does it). > > if my remember is correct, we got bug report that LTP may makes misteriou= s > OOM killer invocation about 1-2 years ago. because, if too many parocess = are in > reclaim path, all of reclaimable pages can be isolated and last reclaimer= found > the system don't have any reclaimable pages and lead to invoke OOM killer=