Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932627AbXBWS4H (ORCPT ); Fri, 23 Feb 2007 13:56:07 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932619AbXBWS4H (ORCPT ); Fri, 23 Feb 2007 13:56:07 -0500 Received: from brick.kernel.dk ([62.242.22.158]:7953 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933177AbXBWS4E (ORCPT ); Fri, 23 Feb 2007 13:56:04 -0500 Date: Fri, 23 Feb 2007 19:35:40 +0100 From: Jens Axboe To: Suparna Bhattacharya Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Linus Torvalds , Arjan van de Ven , Christoph Hellwig , Andrew Morton , Alan Cox , Ulrich Drepper , Zach Brown , Evgeniy Polyakov , "David S. Miller" , Davide Libenzi , Thomas Gleixner Subject: Re: A quick fio test (was Re: [patch 00/13] Syslets, "Threadlets", generic AIO support, v3) Message-ID: <20070223183540.GB22586@kernel.dk> References: <20070221211355.GA7302@elte.hu> <20070223125247.GO5737@kernel.dk> <20070223135525.GA31569@in.ibm.com> <20070223145826.GA32465@elte.hu> <20070223151515.GA12960@in.ibm.com> <20070223162508.GA16782@kernel.dk> <20070223171348.GA27838@in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070223171348.GA27838@in.ibm.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2318 Lines: 58 On Fri, Feb 23 2007, Suparna Bhattacharya wrote: > On Fri, Feb 23, 2007 at 05:25:08PM +0100, Jens Axboe wrote: > > On Fri, Feb 23 2007, Suparna Bhattacharya wrote: > > > On Fri, Feb 23, 2007 at 03:58:26PM +0100, Ingo Molnar wrote: > > > > > > > > * Suparna Bhattacharya wrote: > > > > > > > > > As a really crude (and not very realistic) example of the potential > > > > > impact of large numbers of outstanding IOs, I tried some quick direct > > > > > IO comparisons using fio: > > > > > > > > > > [global] > > > > > ioengine=syslet-rw > > > > > buffered=0 > > > > > rw=randread > > > > > bs=64k > > > > > size=1024m > > > > > iodepth=64 > > > > > > > > could you please try those iodepth=20000 tests with the latest > > > > fio-testing branch of fio as well? Jens wrote a new, smarter syslet > > > > plugin for FIO. You'll need the v3 syslet kernel plus: > > > > > > > > git-clone git://git.kernel.dk/data/git/fio.git > > > > cd fio > > > > git-checkout syslet-testing > > > > > > > > my expectation is that it should behave better with iodepth=20000 > > > > (although i havent tried that yet). > > > > > > I picked up the fio snapshot from 22nd Feb (fio-git-20070222212513.tar.gz) > > > and used the v3 syslet patches from your web-site. > > > > > > Do I still need to get something more recent ? > > > > Yes, you need to test the syslet+testing branch that Ingo referenced. > > Your test above is not totally fair right now, since you are doing > > significantly less system calls with libaio. So to compare apples with > > apples, try the syslet-testing branch. If you can't get it because of > > firewall problems, check http://brick.kernel.dk/snaps/ for the latest > > fio snapshot. If it has the syslet-testing branch, then that is > > recent enough. > > I have a feeling this is getting to be a little more bleeding edge than > I had anticipated :), so will just hold off for a bit until this > crystallizes a bit. Fair enough, I'll try your test with a huge number of pending requests and see how it fares. -- 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/