Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266810AbUIIXVv (ORCPT ); Thu, 9 Sep 2004 19:21:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268054AbUIIXVu (ORCPT ); Thu, 9 Sep 2004 19:21:50 -0400 Received: from holomorphy.com ([207.189.100.168]:26804 "EHLO holomorphy.com") by vger.kernel.org with ESMTP id S266810AbUIIXVD (ORCPT ); Thu, 9 Sep 2004 19:21:03 -0400 Date: Thu, 9 Sep 2004 16:20:53 -0700 From: William Lee Irwin III To: Alan Cox Cc: Andrew Morton , Ingo Molnar , rlrevell@joe-job.com, Linux Kernel Mailing List , felipe_alfaro@linuxmail.org, mista.tapas@gmx.net, kr@cybsft.com, Mark_H_Johnson@Raytheon.com Subject: Re: [patch] voluntary-preempt-2.6.9-rc1-bk12-R6 Message-ID: <20040909232053.GP3106@holomorphy.com> Mail-Followup-To: William Lee Irwin III , Alan Cox , Andrew Morton , Ingo Molnar , rlrevell@joe-job.com, Linux Kernel Mailing List , felipe_alfaro@linuxmail.org, mista.tapas@gmx.net, kr@cybsft.com, Mark_H_Johnson@Raytheon.com References: <20040903120957.00665413@mango.fruits.de> <20040904195141.GA6208@elte.hu> <20040905140249.GA23502@elte.hu> <20040906110626.GA32320@elte.hu> <1094626562.1362.99.camel@krustophenia.net> <20040909192924.GA1672@elte.hu> <20040909130526.2b015999.akpm@osdl.org> <20040909224535.GN3106@holomorphy.com> <1094767887.15731.0.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1094767887.15731.0.camel@localhost.localdomain> Organization: The Domain of Holomorphy User-Agent: Mutt/1.5.6+20040722i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1363 Lines: 26 On Iau, 2004-09-09 at 23:45, William Lee Irwin III wrote: >> Something odd is going on, in part because I get *blistering* IO speeds >> running benchmarks like dbench, tiobench, et al on tmpfs with striped >> swap. In fact, IO speeds markedly faster than any other filesystem I've >> ever tried, by about 30MB/s (i.e. wirespeed, where others fall about >> 37.5% short of it). Virtual alignment issues do hurt, but the core >> allocation algorithm appears to be better than good, it's astounding. On Thu, Sep 09, 2004 at 11:11:39PM +0100, Alan Cox wrote: > Thats a very atypical load where you can expect to get long linear write > outs. The seek v write numbers for a disk nowdays have more in common > with a tape drive. Paging tends to be much much more random. Yes, I mentioned that those kinds of benchmarks are not the workload we're shooting for in the second part of the message. The commentary regarding dbench et al on tmpfs suggests that the lower-level parts of the algorithm are sound, but are somehow driven inappropriately or in a manner unaligned with what locality of reference there may be. -- wli - 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/