Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 10 Jul 2001 13:01:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 10 Jul 2001 13:01:35 -0400 Received: from isimail.interactivesi.com ([207.8.4.3]:22542 "HELO dinero.interactivesi.com") by vger.kernel.org with SMTP id ; Tue, 10 Jul 2001 13:01:21 -0400 Message-ID: <3B4B34D9.8090203@interactivesi.com> Date: Tue, 10 Jul 2001 12:01:13 -0500 From: Timur Tabi Organization: Interactive Silicon User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.2) Gecko/20010628 X-Accept-Language: en-us MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: Re: What is the truth about Linux 2.4's RAM limitations? In-Reply-To: <200107092129.QAA13628@tomcat.admin.navo.hpc.mil> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-AntiVirus: scanned for viruses by AMaViS 0.2.1 (http://amavis.org/) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jesse Pollard wrote: >>So what are the limits without using PAE? Here I'm still having a little >>problem finding definitive answers but ... >> >3 GB. Final answers are in the FAQ, and have been discussed before. You can >also look in the Intel 80x86 CPU specifications. > >The only way to exceed current limits is via some form of segment register usage >which will require a different compiler and a replacement of the memory >architecture of x86 Linux implementation. > Are you talking about using 48-bit pointers? (48-bit pointers, aka 16:32 pointers, on x86 are basically "far 32-bit pointers". That is, each pointer is stored as a 48-bit value, where 16 bits are for the selector/segment, and 32 bits are for the offset. -- Timur Tabi Interactive Silicon - 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/