Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757927AbZDCHZ0 (ORCPT ); Fri, 3 Apr 2009 03:25:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751334AbZDCHZL (ORCPT ); Fri, 3 Apr 2009 03:25:11 -0400 Received: from brick.kernel.dk ([93.163.65.50]:46353 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750949AbZDCHZK (ORCPT ); Fri, 3 Apr 2009 03:25:10 -0400 Date: Fri, 3 Apr 2009 09:25:07 +0200 From: Jens Axboe To: Linus Torvalds Cc: Lennart Sorensen , Ingo Molnar , Andrew Morton , tytso@mit.edu, drees76@gmail.com, jesper@krogh.cc, Linux Kernel Mailing List Subject: Re: Linux 2.6.29 Message-ID: <20090403072507.GO5178@kernel.dk> References: <20090326171148.9bf8f1ec.akpm@linux-foundation.org> <20090326174704.cd36bf7b.akpm@linux-foundation.org> <20090326182519.d576d703.akpm@linux-foundation.org> <20090401210337.GB3797@csclub.uwaterloo.ca> <20090401143622.b1885643.akpm@linux-foundation.org> <20090402010044.GA16092@elte.hu> <20090403040649.GF3795@csclub.uwaterloo.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1966 Lines: 54 On Thu, Apr 02 2009, Linus Torvalds wrote: > > Jens - remind us what the problem with AS was wrt CFQ? CFQ was just faster, plus it supported things like io priorities that AS does not. > There's some write throttling in CFQ, maybe it has some really broken > case? Who knows, it's definitely interesting and something to look into why AS performs that differently to CFQ on his box. Lennart, can you give some information on what file system + mount options, disk drive(s), etc? A full dmesg would be good, too. > > Linus > > On Fri, 3 Apr 2009, Lennart Sorensen wrote: > > > On Thu, Apr 02, 2009 at 03:00:44AM +0200, Ingo Molnar wrote: > > > I'll test this (and the other suggestions) once i'm out of the merge > > > window. > > > > > > I probably wont test that though ;-) > > > > > > Going back to v2.6.14 to do pre-mutex-merge performance tests was > > > already quite a challenge on modern hardware. > > > > Well after a day of running my mythtv box with anticipatiry rather than > > the default cfq scheduler, it certainly looks a lot better. I haven't > > seen any slowdowns, the disk activity light isn't on solidly (it just > > flashes every couple of seconds instead), and it doesn't even mind > > me lanuching bittornado on multiple torrents at the same time as two > > recordings are taking place and some commercial flagging is taking place. > > With cfq this would usually make the system unusable (and a Q6600 with > > 6GB ram should never be unresponsive in my opinion). > > > > So so far I would rank anticipatory at about 1000x better than cfq for > > my work load. It sure acts a lot more like it used to back in 2.6.18 > > times. > > > > -- > > Len Sorensen > > -- Jens Axboe -- 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/