Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161485AbWATEJZ (ORCPT ); Thu, 19 Jan 2006 23:09:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161486AbWATEJZ (ORCPT ); Thu, 19 Jan 2006 23:09:25 -0500 Received: from out4.smtp.messagingengine.com ([66.111.4.28]:63112 "EHLO out4.smtp.messagingengine.com") by vger.kernel.org with ESMTP id S1161485AbWATEJY (ORCPT ); Thu, 19 Jan 2006 23:09:24 -0500 X-Sasl-enc: QyZkrN6j/7xd1md+PIXzW/jg71Zaafoq65x61cH9IV1h 1137730160 Message-ID: <43D0626A.2090802@fastmail.co.uk> Date: Fri, 20 Jan 2006 12:09:14 +0800 From: Max Waterman User-Agent: Thunderbird 1.6a1 (Macintosh/20060117) MIME-Version: 1.0 To: linux-kernel@vger.kernel.org CC: Alan Cox Subject: Re: io performance... References: <5vx8f-1Al-21@gated-at.bofh.it> <5wbRY-3cF-3@gated-at.bofh.it> <5wdKh-5wF-15@gated-at.bofh.it> <43CEF263.9060102@shaw.ca> <43CF90C6.8050505@fastmail.co.uk> <1137679698.8471.30.camel@localhost.localdomain> In-Reply-To: <1137679698.8471.30.camel@localhost.localdomain> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 753 Lines: 20 Alan Cox wrote: > On Iau, 2006-01-19 at 21:14 +0800, Max Waterman wrote: >> So, if I have my raid controller set to use write-back, it *is* caching >> the writes, and so this *is* a bad thing, right? > > Depends on your raid controller. If it is battery backed it may well all > be fine. Eh? Why? I'm not sure what difference it makes if the controller is battery backed or not; if the drives are gone, then the card has nothing to write to...will it make the writes when the power comes back on? Max. - 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/