From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750811AbWAJNns (ORCPT ); Tue, 10 Jan 2006 08:43:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750822AbWAJNnr (ORCPT ); Tue, 10 Jan 2006 08:43:47 -0500 Received: from winds.org ([68.75.195.9]:4831 "EHLO winds.org") by vger.kernel.org with ESMTP id S1750811AbWAJNnr (ORCPT ); Tue, 10 Jan 2006 08:43:47 -0500 Date: Tue, 10 Jan 2006 08:43:33 -0500 (EST) From: Byron Stanoszek To: Jens Axboe cc: Ingo Molnar , linux-kernel@vger.kernel.org, Andrew Morton , Linus Torvalds Subject: Re: 2G memory split In-Reply-To: <20060110133728.GB3389@suse.de> Message-ID: References: <20060110125852.GA3389@suse.de> <20060110132957.GA28666@elte.hu> <20060110133728.GB3389@suse.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 10 Jan 2006, Jens Axboe wrote: >> yes, i made it totally configurable in 2.4 days: 1:3, 2/2 and 3:1 splits >> were possible. It was a larger patch to enable all this across x86, but >> the Kconfig portion was removed a bit later because people _frequently_ >> misconfigured their kernels and then complained about the results. > > How is this different than all other sorts of misconfigurations? As far > as I can tell, the biggest "problem" for some is if they depend on some > binary module that will of course break with a different page offset. > > For simplicity, I didn't add more than the 2/2 split, where we could add > even a 3/1 kernel/user or a 0.5/3.5 (I think sles8 had this). I prefer setting __PAGE_OFFSET to (0x78000000) on machines with 2GB of RAM. This seems to let the kernel use the full 2GB of memory, rather than just 1920-1984 MB (at least back in 2.4 days). -Byron -- Byron Stanoszek Ph: (330) 644-3059 Systems Programmer Fax: (330) 644-8110 Commercial Timesharing Inc. Email: byron@comtime.com