From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751252AbWGXP4Q (ORCPT ); Mon, 24 Jul 2006 11:56:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751217AbWGXP4Q (ORCPT ); Mon, 24 Jul 2006 11:56:16 -0400 Received: from [212.70.63.67] ([212.70.63.67]:6407 "EHLO raad.intranet") by vger.kernel.org with ESMTP id S932202AbWGXP4P (ORCPT ); Mon, 24 Jul 2006 11:56:15 -0400 From: Al Boldi To: linux-kernel@vger.kernel.org Subject: Re: CFQ will be the new default IO scheduler - why? Date: Mon, 24 Jul 2006 18:57:43 +0300 User-Agent: KMail/1.5 Cc: linux-fsdevel@vger.kernel.org MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Message-Id: <200607241857.43399.a1426z@gawab.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Justin Piszcz wrote: > On Mon, 24 Jul 2006, Matthias Andree wrote: > > On Sun, 23 Jul 2006, Paa Paa wrote: > >> The default IO scheduler in 2.6.18 will be CFQ (Complete Fair Queuing) > >> instead of AS (Anticipatory Scheduler) as described here: > >> http://wiki.kernelnewbies.org/Linux_2_6_18. I tried to find (here, at > >> lkml) the discussion about this change with no luck. > > > > That wiki document nicely shows the advantage of the scheduler, namely > > that you have "ionice", which isn't possible for AS or Deadline > > Schedulers - this allows the operating system to run processes like > > updatedb with "nice I/O", meaning these hold when you're doing other > > I/O. > > Should there be a default scheduler per filesystem? As some filesystems > may perform better/worse with one over another? It's currently perDevice, and should probably be extended to perMount. Thanks! -- Al