From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757251AbYESJDT (ORCPT ); Mon, 19 May 2008 05:03:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751448AbYESJDG (ORCPT ); Mon, 19 May 2008 05:03:06 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.31.123]:54415 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751417AbYESJDE (ORCPT ); Mon, 19 May 2008 05:03:04 -0400 Date: Mon, 19 May 2008 11:04:01 +0200 From: Pavel Machek To: Andrew Morton Cc: Eric Sandeen , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, jamie@shareable.org Subject: Re: [PATCH 0/4] (RESEND) ext3[34] barrier changes Message-ID: <20080519090401.GB2013@elf.ucw.cz> References: <482DDA56.6000301@redhat.com> <20080516130545.845a3be9.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080516130545.845a3be9.akpm@linux-foundation.org> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! On Fri 2008-05-16 13:05:45, Andrew Morton wrote: > On Fri, 16 May 2008 14:02:46 -0500 Eric Sandeen wrote: > > > A collection of patches to make ext3 & 4 use barriers by > > default, and to call blkdev_issue_flush on fsync if they > > are enabled. > > Last time this came up lots of workloads slowed down by 30% so I > dropped the patches in horror. > > I just don't think we can quietly go and slow everyone's machines down > by this much. The overhead of journalling is already pretty horrid. > > If we were seeing a significant number of "hey, my disk got wrecked" > reports which attributable to this then yes, perhaps we should change > the default. But I've never seen _any_, although I've seen claims that > others have seen reports. Do you remember seeing "my disk was wrecked" for reiserfs? I believe I got some corruption, but it was a) long time ago b) took half a year of hard powerdowns to provoke c) I did not report it anywhere because ... it just was not reproducible. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html