Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756638AbZC2BZb (ORCPT ); Sat, 28 Mar 2009 21:25:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752435AbZC2BZW (ORCPT ); Sat, 28 Mar 2009 21:25:22 -0400 Received: from srv5.dvmed.net ([207.36.208.214]:47107 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751795AbZC2BZV (ORCPT ); Sat, 28 Mar 2009 21:25:21 -0400 Message-ID: <49CECDEB.7040704@garzik.org> Date: Sat, 28 Mar 2009 21:24:59 -0400 From: Jeff Garzik User-Agent: Thunderbird 2.0.0.21 (X11/20090320) MIME-Version: 1.0 To: david@lang.hm CC: Linus Torvalds , Matthew Garrett , Alan Cox , Theodore Tso , Andrew Morton , David Rees , Jesper Krogh , Linux Kernel Mailing List Subject: Re: Linux 2.6.29 References: <20090327051338.GP6239@mit.edu> <20090327055750.GA18065@srcf.ucam.org> <20090327062114.GA18290@srcf.ucam.org> <20090327112438.GQ6239@mit.edu> <20090327145156.GB24819@srcf.ucam.org> <20090327150811.09b313f5@lxorguk.ukuu.org.uk> <20090327152221.GA25234@srcf.ucam.org> <20090327161553.31436545@lxorguk.ukuu.org.uk> <20090327162841.GA26860@srcf.ucam.org> <20090327165150.7e69d9e1@lxorguk.ukuu.org.uk> <20090327170208.GA27646@srcf.ucam.org> <49CD2C47.4040300@garzik.org> <49CD4DDF.3000001@garzik.org> <49CD7B10.7010601@garzik.org> In-Reply-To: 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: 1239 Lines: 30 david@lang.hm wrote: > ted's suggestion (in his blog) to tweak fsync to 'misbehave' when laptop > mode is enabled (only pushing data out to disk when the disk is awake > anyway, or the time has hit) would really work well for most users. > servers (where you have the data integrity fsync useage) don't use > laptop mode. desktops could use 'laptop mode' with a delay of 0.5 or 1 > second and get prety close the the guarentee that users want without a > huge performance hit. The existential struggle is overall amusing: Application writers start using userland transactional databases for crash recovery and consistency, and in response, OS writers work to undercut the consistency guarantees currently provided by the OS. More seriously, if we get sqlite, db4 and a few others behaving sanely WRT fsync, you cover a wide swath of apps all at once. I absolutely agree that db4, sqlite and friends need to be smarter in the case of laptop mode or overall power saving. 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/