Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754354AbYF2WMa (ORCPT ); Sun, 29 Jun 2008 18:12:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751995AbYF2WMV (ORCPT ); Sun, 29 Jun 2008 18:12:21 -0400 Received: from ipmail04.adl2.internode.on.net ([203.16.214.57]:50338 "EHLO ipmail04.adl2.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751888AbYF2WMU (ORCPT ); Sun, 29 Jun 2008 18:12:20 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApoEANexXkh5LFnm/2dsb2JhbACuPg X-IronPort-AV: E=Sophos;i="4.27,724,1204464600"; d="scan'208";a="145965177" Date: Mon, 30 Jun 2008 08:12:17 +1000 From: Dave Chinner To: xfs-masters@oss.sgi.com Cc: Elias Oltmanns , Henrique de Moraes Holschuh , Kyle Moffett , "Rafael J. Wysocki" , Matthew Garrett , David Chinner , Jeremy Fitzhardinge , Linux Kernel Mailing List Subject: Re: [xfs-masters] Re: freeze vs freezer Message-ID: <20080629221217.GM29319@disturbed> Mail-Followup-To: xfs-masters@oss.sgi.com, Elias Oltmanns , Henrique de Moraes Holschuh , Kyle Moffett , "Rafael J. Wysocki" , Matthew Garrett , David Chinner , Jeremy Fitzhardinge , Linux Kernel Mailing List References: <4744FD87.7010301@goop.org> <200711262253.35420.rjw@sisk.pl> <20071127053846.GA28884@srcf.ucam.org> <200711271840.24825.rjw@sisk.pl> <8B00F353-983F-40E7-931B-EA73CCD32F0A@mac.com> <20080623071601.GA1553@elf.ucw.cz> <20080623140012.GA11899@khazad-dum.debian.net> <87od5rs1am.fsf@denkblock.local> <20080626150910.GK5642@ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080626150910.GK5642@ucw.cz> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1451 Lines: 36 On Thu, Jun 26, 2008 at 05:09:10PM +0200, Pavel Machek wrote: > > > Is this the same thing the per-device IO-queue-freeze patches for > > >HDAPS also > > > need to do? If so, you may want to talk to Elias Oltmanns > > > about it. Added to CC. > > > > Thanks for the heads up Henrique. Even though these issues seem to be > > related up to a certain degree, there probably are some important > > differences. When suspending a system, the emphasis is on leaving the > > system in a consistent state (think of journalled file systems), whereas > > disk shock protection is mainly concerned with stopping I/O as soon as > > possible. As yet, I cannot possibly say to what extend these two > > concepts can be reconciled in the sense of sharing some common code. > > Actually, I believe requirements are same. > > 'don't do i/o in dangerous period'. > > swsusp will just do sync() before entering dangerous period. That > provides consistent-enough state... As I've said many times before - if the requirement is "don't do I/O" then you have to freeze the filesystem. In no way does 'sync' prevent filesystems from doing I/O..... Cheers, Dave. -- Dave Chinner david@fromorbit.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/