From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: [RFT] major libata update Date: Thu, 18 May 2006 08:52:07 -0400 Message-ID: <446C6DF7.6030202@pobox.com> References: <20060515170006.GA29555@havoc.gtf.org> <4469B93E.6010201@emc.com> <4469E0DB.1040709@garzik.org> <4469EEC0.4060907@gmail.com> <446A1A21.80501@emc.com> <446A63F6.5030706@gmail.com> <446A6615.6050701@garzik.org> <446A678E.8030403@garzik.org> <446A6ECD.7080104@garzik.org> <446A734A.6020504@gmail.com> <446A7504.9000201@gmail.com> <446A88DF.5060705@emc.com> <446A7E4A.1080003@gmail.com> <446A9F13.4020907@emc.com> <446AAA33.5010800@gmail.com> <446B8F25.3040907@pobox.com> <446B8FC6.5040009@garzik.org> <446B9AA7.4000305@gmail.com> <446B9C1A.1060106@rtr.ca> <446BEB11.4030703@emc.com> <446BE97A.2080303@gmail.com> <446C6163.7010002@emc.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from proof.pobox.com ([207.106.133.28]:33420 "EHLO proof.pobox.com") by vger.kernel.org with ESMTP id S1751096AbWERMw3 (ORCPT ); Thu, 18 May 2006 08:52:29 -0400 In-Reply-To: <446C6163.7010002@emc.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Ric Wheeler Cc: Tejun Heo , Mark Lord , Jeff Garzik , linux-ide@vger.kernel.org, Jens Axboe > > A different discussion is what we should do or log when we detect this - i.e., write cache enabled and barrier ops not supported (disable write cache? log a scarier message? ignore it?). Today's behavior is probably what most home users want (run as fast as I can, absolute data integrity over power failures not a big deal) but not the right behavior for critical data (i.e., forget performance, make sure my data is always safe ). Yes, 99.99% of Linux users would really complain like mad if the *kernel* took over the *policy* decision of disabling write-caching. The long-term kernel rule has always been, leave *policy* to user-space. Cheers -- Mark Lord Real-Time Remedies Inc. mlord@pobox.com