Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752108AbZCYJj0 (ORCPT ); Wed, 25 Mar 2009 05:39:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752990AbZCYJjR (ORCPT ); Wed, 25 Mar 2009 05:39:17 -0400 Received: from brick.kernel.dk ([93.163.65.50]:50796 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753482AbZCYJjQ (ORCPT ); Wed, 25 Mar 2009 05:39:16 -0400 Date: Wed, 25 Mar 2009 10:39:13 +0100 From: Jens Axboe To: Jeff Garzik Cc: Linus Torvalds , Theodore Tso , Ingo Molnar , Alan Cox , Arjan van de Ven , Andrew Morton , Peter Zijlstra , Nick Piggin , David Rees , Jesper Krogh , Linux Kernel Mailing List Subject: Re: Linux 2.6.29 Message-ID: <20090325093913.GJ27476@kernel.dk> References: <72dbd3150903232346g5af126d7sb5ad4949a7b5041f@mail.gmail.com> <20090324091545.758d00f5@lxorguk.ukuu.org.uk> <20090324093245.GA22483@elte.hu> <20090324101011.6555a0b9@lxorguk.ukuu.org.uk> <20090324103111.GA26691@elte.hu> <20090324132032.GK5814@mit.edu> <20090324184549.GE32307@mit.edu> <49C93AB0.6070300@garzik.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <49C93AB0.6070300@garzik.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1349 Lines: 37 On Tue, Mar 24 2009, Jeff Garzik wrote: > Linus Torvalds wrote: >> But I really don't understand filesystem people who think that "fsck" >> is the important part, regardless of whether the data is valid or not. >> That's just stupid and _obviously_ bogus. > > I think I can understand that point of view, at least: > > More customers complain about hours-long fsck times than they do about > silent data corruption of non-fsync'd files. > > >> The point is, if you write your metadata earlier (say, every 5 sec) and >> the real data later (say, every 30 sec), you're actually MORE LIKELY to >> see corrupt files than if you try to write them together. >> >> And if you write your data _first_, you're never going to see >> corruption at all. > > Amen. > > And, personal filesystem pet peeve: please encourage proper FLUSH CACHE > use to give users the data guarantees they deserve. Linux's sync(2) and > fsync(2) (and fdatasync, etc.) should poke the block layer to guarantee > a media write. fsync already does that, at least if you have barriers enabled on your drive. -- Jens Axboe -- 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/