Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756055AbZDQTrU (ORCPT ); Fri, 17 Apr 2009 15:47:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752993AbZDQTrJ (ORCPT ); Fri, 17 Apr 2009 15:47:09 -0400 Received: from smtp-vbr5.xs4all.nl ([194.109.24.25]:1455 "EHLO smtp-vbr5.xs4all.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751600AbZDQTrH (ORCPT ); Fri, 17 Apr 2009 15:47:07 -0400 Date: Fri, 17 Apr 2009 21:46:46 +0200 From: Folkert van Heusden To: Mark Lord Cc: Andi Kleen , Anton Ertl , linux-kernel@vger.kernel.org Subject: Re: Out-of-order writing by disk drives Message-ID: <20090417194646.GC10554@vanheusden.com> References: <87r5zv72cl.fsf@basil.nowhere.org> <20090414172406.GX14687@one.firstfloor.org> <49E4CA75.902@rtr.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <49E4CA75.902@rtr.ca> Organization: www.unixexpert.nl X-Chameleon-Return-To: folkert@vanheusden.com X-Xfmail-Return-To: folkert@vanheusden.com X-Phonenumber: +31-6-41278122 X-URL: http://www.vanheusden.com/ X-PGP-KeyID: 1F28D8AE X-GPG-fingerprint: AC89 09CE 41F2 00B4 FCF2 B174 3019 0E8C 1F28 D8AE X-Key: http://pgp.surfnet.nl:11371/pks/lookup?op=get&search=0x1F28D8AE Read-Receipt-To: Reply-By: Sat Apr 18 21:15:00 CEST 2009 X-Message-Flag: www.vanheusden.com User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1241 Lines: 30 >> A full listing of what devices do and don't support barriers would >> be likely very long. You would actually need to list down to hard disks. >> >> A common problem is barriers over LVM. Since 2.6.29 they work >> with a single device (and if the underlying device supports it) with >> dm linear, but not in any other LVM setup. > .. > > Does anyone else here find this rather peculiar? > The folks who actually care about barriers the most > (apart from kernel developers) are probably enterprise users. > And who is most likely to be using RAID and LVM, > where barriers generally don't work at all ? What about iSCSI? Does it support barriers? Folkert van Heusden -- MultiTail cok yonlu kullanimli bir program, loglari okumak, verilen kommandolari yerine getirebilen. Filter, renk verme, merge, 'diff- view', vs. http://www.vanheusden.com/multitail/ ---------------------------------------------------------------------- Phone: +31-6-41278122, PGP-key: 1F28D8AE, www.vanheusden.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/