From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932925AbZJGMKX (ORCPT ); Wed, 7 Oct 2009 08:10:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932850AbZJGMKW (ORCPT ); Wed, 7 Oct 2009 08:10:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52079 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932839AbZJGMKV (ORCPT ); Wed, 7 Oct 2009 08:10:21 -0400 From: Jeff Moyer To: Jens Axboe Cc: zach.brown@oracle.com, linux-aio , Linux Kernel Mailing , Andrew Morton Subject: Re: [patch v4 0/3] aio: implement request batching [more performance numbers] References: <20091006180628.GB5216@kernel.dk> <20091007105259.GD8703@kernel.dk> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 X-PCLoadLetter: What the f**k does that mean? Date: Wed, 07 Oct 2009 08:09:10 -0400 In-Reply-To: <20091007105259.GD8703@kernel.dk> (Jens Axboe's message of "Wed, 7 Oct 2009 12:52:59 +0200") Message-ID: User-Agent: Gnus/5.110011 (No Gnus v0.11) Emacs/23.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jens Axboe writes: > So here's a pretty basic test. It does random reads from a bunch of > devices, I tested both 4kb and 64kb block sizes. Queue depth used is 32 > for both cases, but note that this test uses a thread per device (so the > queue depth is 32 per device). Results are averaged over 3 runs. > slat/clat are the submission and completion latencies, they are in > microseconds here. > > 4kb random reads > > kernel sys IOPS slat clat > ---------------------------------------------------- > 2.6.32-rc3+patch 25.8% 192500 7.9 2606 > 2.6.32-rc3 27.4% 191300 8.4 2612 > > > > 64kb random reads > > kernel sys IOPS slat clat > ---------------------------------------------------- > 2.6.32-rc3+patch 2.5% 24590 9.7 9681 > 2.6.32-rc3 2.5% 24580 9.4 9691 > > So pretty close, nothing earth shattering here. What the results above > do not show is that the 4kb test runs very stable with your patch. > Mainline fluctuates somewhat in the bandwidth, most likely due to the > varying depth. OK, good news. Thanks for testing! Cheers, Jeff