Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754160AbYAPLvv (ORCPT ); Wed, 16 Jan 2008 06:51:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753847AbYAPLvk (ORCPT ); Wed, 16 Jan 2008 06:51:40 -0500 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:42769 "EHLO amd.ucw.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753810AbYAPLvi (ORCPT ); Wed, 16 Jan 2008 06:51:38 -0500 Date: Wed, 16 Jan 2008 12:51:44 +0100 From: Pavel Machek To: Daniel Phillips Cc: David Chinner , Alan Cox , Theodore Tso , Al Boldi , Valerie Henson , Rik van Riel , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [Patch] document ext3 requirements (was Re: [RFD] Incremental fsck) Message-ID: <20080116115144.GE22460@elf.ucw.cz> References: <200801090740.12989.a1426z@gawab.com> <70b6f0bf0801082345vf57951ey642e35c3d6e5194f@mail.gmail.com> <200801091452.14890.a1426z@gawab.com> <20080112145140.GB6751@mit.edu> <20080113171916.GB4132@ucw.cz> <20080113174125.5f39ac64@lxorguk.ukuu.org.uk> <20080115201653.GA5639@elf.ucw.cz> <20080115214325.GN155407@sgi.com> <20080115230714.GC3573@elf.ucw.cz> <4d47a5d10801151544k3bc50223ob69c25d8732e3f12@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4d47a5d10801151544k3bc50223ob69c25d8732e3f12@mail.gmail.com> 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 Content-Length: 1118 Lines: 25 On Tue 2008-01-15 18:44:26, Daniel Phillips wrote: > On Jan 15, 2008 6:07 PM, Pavel Machek wrote: > > I had write cache enabled on my main computer. Oops. I guess that > > means we do need better documentation. > > Writeback cache on disk in iteself is not bad, it only gets bad if the > disk is not engineered to save all its dirty cache on power loss, > using the disk motor as a generator or alternatively a small battery. > It would be awfully nice to know which brands fail here, if any, > because writeback cache is a big performance booster. Is it? I guess I should try to measure it. (Linux already does writeback caching, with 2GB of memory. I wonder how important disks's 2MB of cache can be). Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- 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/