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 06CFF8D0039 for ; Mon, 31 Jan 2011 17:40:27 -0500 (EST) Received: from d03relay03.boulder.ibm.com (d03relay03.boulder.ibm.com [9.17.195.228]) by e37.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id p0VMbmwC030852 for ; Mon, 31 Jan 2011 15:37:48 -0700 Received: from d03av03.boulder.ibm.com (d03av03.boulder.ibm.com [9.17.195.169]) by d03relay03.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p0VMeHOI112580 for ; Mon, 31 Jan 2011 15:40:17 -0700 Received: from d03av03.boulder.ibm.com (loopback [127.0.0.1]) by d03av03.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p0VMeHSj020383 for ; Mon, 31 Jan 2011 15:40:17 -0700 Subject: Re: kswapd hung tasks in 2.6.38-rc1 From: Dave Hansen In-Reply-To: <1296507528.7797.4609.camel@nimitz> References: <1150342867.83404.1295513748640.JavaMail.root@zmail06.collab.prod.int.phx2.redhat.com> <1296507528.7797.4609.camel@nimitz> Content-Type: text/plain; charset="ANSI_X3.4-1968" Date: Mon, 31 Jan 2011 14:40:16 -0800 Message-ID: <1296513616.7797.4929.camel@nimitz> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: CAI Qian Cc: linux-mm , linux-kernel@vger.kernel.org, aarcange List-ID: On Mon, 2011-01-31 at 12:58 -0800, Dave Hansen wrote: > On Thu, 2011-01-20 at 03:55 -0500, CAI Qian wrote: > > When running LTP oom01 [1] testing, the allocation process stopped > > processing right after starting to swap. > > I'm seeing the same stuff, but on -rc2. I thought it was > transparent-hugepage-related, but I don't see much of a trace of it in > the stack dumps. > > http://sr71.net/~dave/ibm/config-v2.6.38-rc2 > > It happened to me as well around the time that things started to hit > swap. Still not a very good data point, but I ran a heavy swap load for an hour or so without reproducing this. But, it happened again after I enabled transparent huge pages. I managed to get a sysrq-t dump out of it: http://sr71.net/~dave/ibm/2.6.38-rc2-hang-0.txt khugepaged is one of the three running tasks. Note, I set both its sleep timeouts to zero to stress it out a bit. I'll keep trying to reproduce without THP. -- Dave -- 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 policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org