From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 6 Jun 2001 04:58:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 6 Jun 2001 04:58:12 -0400 Received: from sportingbet.gw.dircon.net ([195.157.147.30]:50948 "HELO sysadmin.sportingbet.com") by vger.kernel.org with SMTP id ; Wed, 6 Jun 2001 04:58:06 -0400 Date: Wed, 6 Jun 2001 09:54:31 +0100 From: Sean Hunter To: Xavier Bestel Cc: linux-kernel@vger.kernel.org Subject: Re: Break 2.4 VM in five easy steps Message-ID: <20010606095431.C15199@dev.sportingbet.com> Mail-Followup-To: Sean Hunter , Xavier Bestel , linux-kernel@vger.kernel.org In-Reply-To: <3B1D5ADE.7FA50CD0@illusionary.com> <3B1D927E.1B2EBE76@uow.edu.au> <20010605231908.A10520@illusionary.com> <991815578.30689.1.camel@nomade> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <991815578.30689.1.camel@nomade>; from xavier.bestel@free.fr on Wed, Jun 06, 2001 at 10:19:30AM +0200 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 06, 2001 at 10:19:30AM +0200, Xavier Bestel wrote: > On 05 Jun 2001 23:19:08 -0400, Derek Glidden wrote: > > On Wed, Jun 06, 2001 at 12:16:30PM +1000, Andrew Morton wrote: > > > "Jeffrey W. Baker" wrote: > > > > > > > > Because the 2.4 VM is so broken, and > > > > because my machines are frequently deeply swapped, > > > > > > The swapoff algorithms in 2.2 and 2.4 are basically identical. > > > The problem *appears* worse in 2.4 because it uses lots > > > more swap. > > > > I disagree with the terminology you're using. It *is* worse in 2.4, > > period. If it only *appears* worse, then if I encounter a situation > > where a 2.2 box has utilized as much swap as a 2.4 box, I should see the > > same results. Yet this happens not to be the case. > > Did you try to put twice as much swap as you have RAM ? (e.g. add a 512M > swapfile to your box) > This is what Linus recommended for 2.4 (swap = 2 * RAM), saying that > anything less won't do any good: 2.4 overallocates swap even if it > doesn't use it all. So in your case you just have enough swap to map > your RAM, and nothing to really swap your apps. > For large memory boxes, this is ridiculous. Should I have 8GB of swap? Sean