Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754530Ab0FZL45 (ORCPT ); Sat, 26 Jun 2010 07:56:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:61511 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754037Ab0FZL4x (ORCPT ); Sat, 26 Jun 2010 07:56:53 -0400 Message-ID: <4C25EAC4.1040909@redhat.com> Date: Sat, 26 Jun 2010 07:55:48 -0400 From: Ric Wheeler User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.10) Gecko/20100621 Fedora/3.0.5-1.fc13 Lightning/1.0b2pre Thunderbird/3.0.5 MIME-Version: 1.0 To: Michael Tokarev CC: Daniel Taylor , Mike Fedyk , Daniel J Blueman , Mat , LKML , linux-fsdevel@vger.kernel.org, Chris Mason , Andrew Morton , Linus Torvalds , The development of BTRFS Subject: Re: Btrfs: broken file system design (was Unbound(?) internal fragmentation in Btrfs) References: <4C07C321.8010000@redhat.com><4C1B7560.1000806@gmail.com><4C1BA3E5.7020400@gmail.com><20100623234031.GF7058@shareable.org><469D2D911E4BF043BFC8AD32E8E30F5B24AEBA@wdscexbe07.sc.wdc.com> <469D2D911E4BF043BFC8AD32E8E30F5B24AEBB@wdscexbe07.sc.wdc.com> <4C24FC71.6020001@redhat.com> <4C258D91.6010308@msgid.tls.msk.ru> In-Reply-To: <4C258D91.6010308@msgid.tls.msk.ru> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1732 Lines: 46 On 06/26/2010 01:18 AM, Michael Tokarev wrote: > 25.06.2010 22:58, Ric Wheeler wrote: > >> On 06/24/2010 06:06 PM, Daniel Taylor wrote: >> > [] > >>>> On Wed, Jun 23, 2010 at 8:43 PM, Daniel Taylor >>>> wrote: >>>> >>>> >>>>> Just an FYI reminder. The original test (2K files) is utterly >>>>> pathological for disk drives with 4K physical sectors, such as >>>>> those now shipping from WD, Seagate, and others. Some of the >>>>> SSDs have larger (16K0 or smaller blocks (2K). There is also >>>>> the issue of btrfs over RAID (which I know is not entirely >>>>> sensible, but which will happen). >>>>> > Why it is not sensible to use btrfs on raid devices? > Nowadays raid is just everywhere, from 'fakeraid' on AHCI to > large external arrays on iSCSI-attached storage. Sometimes > it is nearly imposisble to _not_ use RAID, -- many servers > comes with a built-in RAID card which can't be turned off or > disabled. And hardware raid is faster (at least in theory) > at least because it puts less load on various system busses. > > To many "enterprise folks" a statement "we don't need hw raid, > we have better solution" sounds like "we're just a toy, don't > use". > > Hmm? ;) > > /mjt, who always used and preferred _software_ raid due to > multiple reasons, and never used btrfs so far. > Absolutely no reason that you would not use btrfs on hardware raid volumes (or software RAID for that matter). Ric -- 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/