Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761918AbZCaUve (ORCPT ); Tue, 31 Mar 2009 16:51:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753927AbZCaUvZ (ORCPT ); Tue, 31 Mar 2009 16:51:25 -0400 Received: from srv5.dvmed.net ([207.36.208.214]:60186 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752841AbZCaUvY (ORCPT ); Tue, 31 Mar 2009 16:51:24 -0400 Message-ID: <49D281D8.8030203@garzik.org> Date: Tue, 31 Mar 2009 16:49:28 -0400 From: Jeff Garzik User-Agent: Thunderbird 2.0.0.21 (X11/20090320) MIME-Version: 1.0 To: Jens Axboe CC: Linus Torvalds , Theodore Tso , Ingo Molnar , Alan Cox , Arjan van de Ven , Andrew Morton , Peter Zijlstra , Nick Piggin , David Rees , Jesper Krogh , Linux Kernel Mailing List Subject: Re: Linux 2.6.29 References: <20090324093245.GA22483@elte.hu> <20090324101011.6555a0b9@lxorguk.ukuu.org.uk> <20090324103111.GA26691@elte.hu> <20090324132032.GK5814@mit.edu> <20090324184549.GE32307@mit.edu> <49C93AB0.6070300@garzik.org> <20090325093913.GJ27476@kernel.dk> <49CA86BD.6060205@garzik.org> <20090325194341.GB27476@kernel.dk> In-Reply-To: <20090325194341.GB27476@kernel.dk> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -4.4 (----) X-Spam-Report: SpamAssassin version 3.2.5 on srv5.dvmed.net summary: Content analysis details: (-4.4 points, 5.0 required) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1084 Lines: 28 Jens Axboe wrote: > Another problem is that FLUSH_CACHE sucks. Really. And not just on > ext3/ordered, generally. Write a 50 byte file, fsync, flush cache and > wit for the world to finish. Pretty hard to teach people to use a nicer > fdatasync(), when the majority of the cost now becomes flushing the > cache of that 1TB drive you happen to have 8 partitions on. Good luck > with that. (responding to an email way back near the start of the thread) I emailed Microsoft about their proposal to add a WRITE BARRIER command to ATA, documented at http://www.t13.org/Documents/UploadedDocuments/docs2007/e07174r0-Write_Barrier_Command_Proposal.doc The MSFT engineer said they were definitely still pursuing this proposal. IMO we could look at this too, or perhaps come up with an alternate proposal like FLUSH CACHE RANGE(s). Jeff -- 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/