From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265896AbUBCG4Z (ORCPT ); Tue, 3 Feb 2004 01:56:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265899AbUBCG4Z (ORCPT ); Tue, 3 Feb 2004 01:56:25 -0500 Received: from [212.5.174.154] ([212.5.174.154]:36274 "EHLO zelcom.ru") by vger.kernel.org with ESMTP id S265896AbUBCG4Y (ORCPT ); Tue, 3 Feb 2004 01:56:24 -0500 Date: Tue, 03 Feb 2004 09:55:11 +0300 Message-ID: <87smhsy7n4.wl@canopus.ns.zel.ru> From: Samium Gromoff To: akpm@osdl.org CC: linux-kernel@vger.kernel.org, philip@codematters.co.uk Subject: Re: 2.6.1 slower than 2.4, smp/scsi/sw-raid/reiserfs User-Agent: Wanderlust/2.10.1 (Watching The Wheels) SEMI/1.14.5 (Awara-Onsen) FLIM/1.14.5 (Demachiyanagi) APEL/10.6 Emacs/21.3 (i386-pc-linux-gnu) MULE/5.0 (SAKAKI) MIME-Version: 1.0 (generated by SEMI 1.14.5 - "Awara-Onsen") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > > The machine is a dual P3 450MHz, 512MB, aic7xxx, 2 disk RAID-0 and > > ReiserFS. It's a few years old and has always run Linux, most > > recently 2.4.24. I decided to try 2.6.1 and the performance is > > disappointing. > > 2.6 has a few performance problems under heavy pageout at present. Nick > Piggin has some patches which largely fix it up. I`m sorry, but this is misguiding. 2.6 does not have a few performance problems under heavy pageout. It`s more like _systematical_ _performance_ _degradation_ increasing with the pageout rate. The more the box pages out the more 2.6 lags behind 2.4. What i`m trying to say is that even light paging is affected. And light paging is warranted when you run, say, KDE on 128M ram. Go measure the X desktop startup time on a 48M/64M boxen--even light paging causes 2.6 to be just sloower. Also the vm thrashing point is much much earlier. Ask Roger Luethi for details. regards, Samium Gromoff