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 05:29:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 6 Jun 2001 05:29:05 -0400 Received: from sportingbet.gw.dircon.net ([195.157.147.30]:268 "HELO sysadmin.sportingbet.com") by vger.kernel.org with SMTP id ; Wed, 6 Jun 2001 05:28:48 -0400 Date: Wed, 6 Jun 2001 10:25:14 +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: <20010606102514.E15199@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> <20010606095431.C15199@dev.sportingbet.com> <991818989.30690.2.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: <991818989.30690.2.camel@nomade>; from xavier.bestel@free.fr on Wed, Jun 06, 2001 at 11:16:27AM +0200 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 06, 2001 at 11:16:27AM +0200, Xavier Bestel wrote: > On 06 Jun 2001 09:54:31 +0100, Sean Hunter wrote: > > > 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? > > Life is tough. If guess if you have 4GB RAM, you'd be better having no > swap at all. Or, yes, at least 8GB. > Or just wait for this bug to be fixed. But be patient. This is just pure bollocks. Virtual memory is one of the killer features of unix. It would be a strange admission to say that our "advanced" 2.4 kernel is so advanced that now you can't use virtual memory at all on large machines. Needing 8GB of swap to prevent a box from committing suicide when it has a working set of less than 512M is crazy. I am waiting patiently for the bug to be fixed. However, it is a real embarrasment that we can't run this "stable" kernel in production yet because somethign as fundamental as this is so badly broken. Sean