From: "Rafael J. Wysocki" Subject: Re: [PATCH] PM / Freezer: Freeze filesystems while freezing processes (v2) Date: Wed, 16 Nov 2011 22:50:41 +0100 Message-ID: <201111162250.42080.rjw@sisk.pl> References: <4E1C70AD.1010101@u-club.de> <201110222335.29573.rjw@sisk.pl> <874ny4jhy4.fsf@tac.ki.iif.hu> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: Christoph , "Theodore Ts'o" , LKML , xfs@oss.sgi.com, Christoph Hellwig , Nigel Cunningham , Pavel Machek , linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, Linux PM list To: Ferenc Wagner Return-path: Received: from ogre.sisk.pl ([217.79.144.158]:42891 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751744Ab1KPVr7 (ORCPT ); Wed, 16 Nov 2011 16:47:59 -0500 In-Reply-To: <874ny4jhy4.fsf@tac.ki.iif.hu> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Wednesday, November 16, 2011, Ferenc Wagner wrote: > "Rafael J. Wysocki" writes: > > > On Saturday, October 22, 2011, Christoph wrote: > > > >>> PM / Freezer: Freeze filesystems while freezing processes (v2) > >>> > >>> On Sunday, August 07, 2011, Dave Chinner wrote: > >>> > >>>> On Sat, Aug 06, 2011 at 11:17:18PM +0200, Rafael J. Wysocki wrote: > >>>> > >>>>> From: Rafael J. Wysocki > >>>>> > >>>>> Freeze all filesystems during the freezing of tasks by calling > >>>>> freeze_bdev() for each of them and thaw them during the thawing of > >>>>> tasks with the help of thaw_bdev(). > >>>>> > >>>>> This is needed by hibernation, because some filesystems (e.g. XFS) > >>>>> deadlock with the preallocation of memory used by it if the memory > >>>>> pressure caused by it is too heavy. > >>> > >>> Below is an alternative fix, the changelog pretty much explains the > >>> idea. > >>> > >>> I've tested it on Toshiba Portege R500, but I don't have an XFS > >>> partition to verify that it really helps, so I'd appreciate it if > >>> someone able to reproduce the original issue could test it and report > >>> back. > >> > >> Well, the kernel bugtracker is still down and I just like to post my > >> experience with kernel (x64) v3.1-rc8/9 + patches. My machine is a > >> MacBookPro, doomed with 4GB RAM running debian. > >> > >> Bug #1 > >> > >> on the way to hibernate, machine hangs on > >> > >> "PM: Preallocating image memory..." > >> > >> this patch worked for me now for weeks: > >> "[PATCH] PM / Freezer: Freeze filesystems while freezing processes (v2)" > >> https://lkml.org/lkml/2011/9/24/77 > > > > This patch is going to be merged into 3.2. > > Hi, > > I was the original reporter of the Bugzilla issue, just didn't know > about this thread until recently. Anyway, I'm running 3.2-rc1 now, > which contains the alternative fix, and I can confirm that it indeed > works: hibernation does not deadlock on my XFS rooted system anymore > during memory preallocation. Thanks everybody for his or her work on > the issue! > > To add something still, preallocation now ends with a couple of seconds > of heavy disk activity, but with several seconds of total inactivity > beforehand. Is this warranted by some CPU intensive task at that stage? Quilte frankly, I have no idea. Thanks, Rafael