From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932349AbWFEBCM (ORCPT ); Sun, 4 Jun 2006 21:02:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932351AbWFEBCM (ORCPT ); Sun, 4 Jun 2006 21:02:12 -0400 Received: from smtp.osdl.org ([65.172.181.4]:10641 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S932349AbWFEBCL (ORCPT ); Sun, 4 Jun 2006 21:02:11 -0400 Date: Sun, 4 Jun 2006 18:02:08 -0700 From: Andrew Morton To: Fengguang Wu Cc: linux-kernel@vger.kernel.org Subject: Re: readahead benchmark Message-Id: <20060604180208.9f678a9b.akpm@osdl.org> In-Reply-To: <349467272.31863@ustc.edu.cn> References: <20060604135011.decdc7c9.akpm@osdl.org> <349467272.31863@ustc.edu.cn> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.17; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 5 Jun 2006 08:28:07 +0800 Fengguang Wu wrote: > On Sun, Jun 04, 2006 at 01:50:11PM -0700, Andrew Morton wrote: > > readahead-kconfig-options.patch > [...] > > It's early days yet - needs heaps more performance testing. The results > > from "Linux Portal" were discouraging. > > I found this mail from the lkml archive, did you happen to have more > results? > Sorry, I had the wrong tester. Voluspa : "Conclusion: On _this_ machine, with _these_ operations, Adaptive Readahead in its current incarnation and default settings is a _loss_." > > There is an interesting (although simple) benchmark of Wu's adaptive > readahead patchset (v12) together with graphs here: > > http://linux.inet.hr/adaptive_readahead_benchmark.html > > In that simple test it definitely looks promising (3x speedup). That's postgreql again. We know there's a problem at present with postgresql. Has anyone tried to fix it, without going and rewriting everything?