Received: with ECARTIS (v1.0.0; list xfs); Thu, 28 Jun 2007 21:56:41 -0700 (PDT) X-Spam-Checker-Version: SpamAssassin 3.2.0-pre1-r499012 (2007-01-23) on oss.sgi.com X-Spam-Level: X-Spam-Status: No, score=0.2 required=5.0 tests=AWL,BAYES_50 autolearn=no version=3.2.0-pre1-r499012 Received: from larry.melbourne.sgi.com (larry.melbourne.sgi.com [134.14.52.130]) by oss.sgi.com (8.12.10/8.12.10/SuSE Linux 0.7) with SMTP id l5T4uXtL005685 for ; Thu, 28 Jun 2007 21:56:35 -0700 Received: from snort.melbourne.sgi.com (snort.melbourne.sgi.com [134.14.54.149]) by larry.melbourne.sgi.com (950413.SGI.8.6.12/950213.SGI.AUTOCF) via ESMTP id OAA02395; Fri, 29 Jun 2007 14:56:06 +1000 Received: from snort.melbourne.sgi.com (localhost [127.0.0.1]) by snort.melbourne.sgi.com (SGI-8.12.5/8.12.5) with ESMTP id l5T4u1eW4779794; Fri, 29 Jun 2007 14:56:02 +1000 (AEST) Received: (from dgc@localhost) by snort.melbourne.sgi.com (SGI-8.12.5/8.12.5/Submit) id l5T4trFW4779809; Fri, 29 Jun 2007 14:55:53 +1000 (AEST) X-Authentication-Warning: snort.melbourne.sgi.com: dgc set sender to dgc@sgi.com using -f Date: Fri, 29 Jun 2007 14:55:53 +1000 From: David Chinner To: Pavel Machek Cc: David Chinner , David Greaves , David Robinson , LVM general discussion and development , "'linux-kernel@vger.kernel.org'" , xfs@oss.sgi.com, linux-pm , LinuxRaid Subject: Re: [linux-lvm] 2.6.22-rc4 XFS fails after hibernate/resume Message-ID: <20070629045553.GN31489@sgi.com> References: <46744065.6060605@dgreaves.com> <4674645F.5000906@gmail.com> <46751D37.5020608@dgreaves.com> <4676390E.6010202@dgreaves.com> <20070618145007.GE85884050@sgi.com> <20070627204924.GA4777@ucw.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070627204924.GA4777@ucw.cz> User-Agent: Mutt/1.4.2.1i X-Virus-Scanned: ClamAV version 0.90, clamav-milter version devel-120207 on oss.sgi.com X-Virus-Status: Clean X-archive-position: 12013 X-ecartis-version: Ecartis v1.0.0 Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com X-original-sender: dgc@sgi.com Precedence: bulk X-list: xfs On Wed, Jun 27, 2007 at 08:49:24PM +0000, Pavel Machek wrote: > Hi! > > > FWIW, I'm on record stating that "sync" is not sufficient to quiesce an XFS > > filesystem for a suspend/resume to work safely and have argued that the only > > Hmm, so XFS writes to disk even when its threads are frozen? They issue async I/O before they sleep and expects processing to be done on I/O completion via workqueues. > > safe thing to do is freeze the filesystem before suspend and thaw it after > > resume. This is why I originally asked you to test that with the other problem > > Could you add that to the XFS threads if it is really required? They > do know that they are being frozen for suspend. We don't suspend the threads on a filesystem freeze - they continue run. A filesystem freeze guarantees the filesystem clean and that the in memory state matches what is on disk. It is not possible for the filesytem to issue I/O or have outstanding I/O when it is in the frozen state, so the state of the threads and/or workqueues does not matter because they will be idle. Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group