Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262681AbTIQGle (ORCPT ); Wed, 17 Sep 2003 02:41:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262683AbTIQGle (ORCPT ); Wed, 17 Sep 2003 02:41:34 -0400 Received: from users.linvision.com ([62.58.92.114]:11655 "EHLO abraracourcix.bitwizard.nl") by vger.kernel.org with ESMTP id S262681AbTIQGld (ORCPT ); Wed, 17 Sep 2003 02:41:33 -0400 Date: Wed, 17 Sep 2003 08:41:03 +0200 From: Rogier Wolff To: Alan Cox Cc: Stephan von Krawczynski , Marcelo Tosatti , neilb@cse.unsw.edu.au, Linux Kernel Mailing List Subject: Re: experiences beyond 4 GB RAM with 2.4.22 Message-ID: <20030917084102.A19276@bitwizard.nl> References: <20030916102113.0f00d7e9.skraw@ithnet.com> <20030916153658.3081af6c.skraw@ithnet.com> <1063722973.10037.65.camel@dhcp23.swansea.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1063722973.10037.65.camel@dhcp23.swansea.linux.org.uk> User-Agent: Mutt/1.3.22.1i Organization: BitWizard.nl Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1395 Lines: 29 On Tue, Sep 16, 2003 at 03:36:14PM +0100, Alan Cox wrote: > I/O is a real pain. Also in some cases it might be interesting to try > using the extra RAM above the 4G boundary as a giant ram disk and using > it as first swap device. 4G? Above 4G? The limit should be configurable a lot earlier. I'd want to configure that on the machines I'm installing tomorrow. 4G RAM, but I'd rather not use the highmem stuff. I think the workload that this machine is likely to get will work very well with this setup. Why does this have the opportunity to work better than just using the 2 or 4G of RAM? Because after you've used the bottom 1G, that might just remain there, requiring lots of IO to go through bounce buffers and memory remappings. By considering the top part of RAM as swap, you'll force the important stuff into the more easily accessable RAM (Compare to fastram as it was called on the Amiga!). Roger. -- ** R.E.Wolff@BitWizard.nl ** http://www.BitWizard.nl/ ** +31-15-2600998 ** *-- BitWizard writes Linux device drivers for any device you may have! --* **** "Linux is like a wigwam - no windows, no gates, apache inside!" **** - 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/