From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765184AbXHFNQF (ORCPT ); Mon, 6 Aug 2007 09:16:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1764114AbXHFNPz (ORCPT ); Mon, 6 Aug 2007 09:15:55 -0400 Received: from 1wt.eu ([62.212.114.60]:1206 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1764092AbXHFNPy (ORCPT ); Mon, 6 Aug 2007 09:15:54 -0400 Date: Mon, 6 Aug 2007 15:12:15 +0200 From: Willy Tarreau To: Ingo Molnar Cc: Alan Cox , Claudio Martins , Jeff Garzik , =?iso-8859-1?Q?J=F6rn?= Engel , Linus Torvalds , Peter Zijlstra , linux-mm@kvack.org, Linux Kernel Mailing List , miklos@szeredi.hu, akpm@linux-foundation.org, neilb@suse.de, dgc@sgi.com, tomoki.sekiyama.qu@hitachi.com, nikita@clusterfs.com, trond.myklebust@fys.uio.no, yingchao.zhou@gmail.com, richard@rsk.demon.co.uk, david@lang.hm Subject: Re: [PATCH 00/23] per device dirty throttling -v8 Message-ID: <20070806131215.GC10999@1wt.eu> References: <20070803123712.987126000@chello.nl> <46B4E161.9080100@garzik.org> <20070804224706.617500a0@the-village.bc.nu> <200708050051.40758.ctpm@ist.utl.pt> <20070805014926.400d0608@the-village.bc.nu> <20070805072805.GB4414@elte.hu> <20070805134640.2c7d1140@the-village.bc.nu> <20070805125847.GC22060@elte.hu> <20070805132925.GA4089@1wt.eu> <20070806065712.GA2818@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070806065712.GA2818@elte.hu> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 06, 2007 at 08:57:12AM +0200, Ingo Molnar wrote: > > * Willy Tarreau wrote: > > > In your example above, maybe it's the opposite, users know they can > > keep a file in /tmp one more week by simply cat'ing it. > > sure - and i'm not arguing that noatime should the kernel-wide default. > In every single patch i sent it was a .config option (and a boot option > _and_ a sysctl option that i think you missed) that a user/distro > enables or disabled. But i think the /tmp argument is not very strong: > /tmp is fundamentally volatile, and you can grow dependencies on pretty > much _any_ aspect of the kernel. So the question isnt "is there impact" > (there is, at least for noatime), the question is "is it still worth > doing it". > > > Changing the kernel in a non-easily reversible way is not kind to the > > users. > > none of my patches did any of that... I did not notice you talked about a sysctl. A sysctl provides the ability to switch the behaviour without rebooting, while both the config option and the command line require a reboot. > anyway, my latest patch doesnt do noatime, it does the "more intelligent > relatime" approach. ... which is not equivalent noatime in the initial example. Regards, Willy