Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758816AbXFQBoX (ORCPT ); Sat, 16 Jun 2007 21:44:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754311AbXFQBoQ (ORCPT ); Sat, 16 Jun 2007 21:44:16 -0400 Received: from twinlark.arctic.org ([207.29.250.54]:33435 "EHLO twinlark.arctic.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753617AbXFQBoP (ORCPT ); Sat, 16 Jun 2007 21:44:15 -0400 Date: Sat, 16 Jun 2007 18:44:14 -0700 (PDT) From: dean gaudet To: David Greaves cc: Neil Brown , Wakko Warner , david@lang.hm, linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org Subject: Re: limits on raid In-Reply-To: <4673E69A.4020309@dgreaves.com> Message-ID: References: <18034.479.256870.600360@notabene.brown> <18034.3676.477575.490448@notabene.brown> <20070616020320.GB2002@animx.eu.org> <18035.23867.576212.859440@notabene.brown> <4673E69A.4020309@dgreaves.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1123 Lines: 30 On Sat, 16 Jun 2007, David Greaves wrote: > Neil Brown wrote: > > On Friday June 15, wakko@animx.eu.org wrote: > > > > > As I understand the way > > > raid works, when you write a block to the array, it will have to read all > > > the other blocks in the stripe and recalculate the parity and write it > > > out. > > > > Your understanding is incomplete. > > Does this help? > [for future reference so you can paste a url and save the typing for code :) ] > > http://linux-raid.osdl.org/index.php/Initial_Array_Creation i fixed a typo and added one more note which i think is quite fair: It is also safe to use --assume-clean if you are performing performance measurements of different raid configurations. Just be sure to rebuild your array without --assume-clean when you decide on your final configuration. -dean - 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/