From owner-freebsd-questions@FreeBSD.ORG Fri Aug 31 04:54:55 2007 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 47BA516A418 for ; Fri, 31 Aug 2007 04:54:55 +0000 (UTC) (envelope-from youshi10@u.washington.edu) Received: from mxout2.cac.washington.edu (mxout2.cac.washington.edu [140.142.33.4]) by mx1.freebsd.org (Postfix) with ESMTP id 29A2E13C465 for ; Fri, 31 Aug 2007 04:54:55 +0000 (UTC) (envelope-from youshi10@u.washington.edu) Received: from smtp.washington.edu (smtp.washington.edu [140.142.33.9] (may be forged)) by mxout2.cac.washington.edu (8.13.7+UW06.06/8.13.7+UW07.06) with ESMTP id l7V3VnEn026690 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 30 Aug 2007 20:31:49 -0700 X-Auth-Received: from [192.168.10.45] (c-24-10-12-194.hsd1.ca.comcast.net [24.10.12.194]) (authenticated authid=youshi10) by smtp.washington.edu (8.13.7+UW06.06/8.13.7+UW07.03) with ESMTP id l7V3VmCw031014 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Thu, 30 Aug 2007 20:31:49 -0700 Message-ID: <46D78BAD.8070502@u.washington.edu> Date: Thu, 30 Aug 2007 20:31:57 -0700 From: Garrett Cooper User-Agent: Thunderbird 2.0.0.6 (Windows/20070728) MIME-Version: 1.0 To: User Bobby , FreeBSD Questions References: <20070830205618.Q11358@susanne.tomatoseed.org> In-Reply-To: <20070830205618.Q11358@susanne.tomatoseed.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-PMX-Version: 5.3.3.310218, Antispam-Engine: 2.5.1.298604, Antispam-Data: 2007.8.30.200928 X-Uwash-Spam: Gauge=IIIIIII, Probability=7%, Report='__CT 0, __CTE 0, __CT_TEXT_PLAIN 0, __HAS_MSGID 0, __MIME_TEXT_ONLY 0, __MIME_VERSION 0, __SANE_MSGID 0, __USER_AGENT 0' Cc: Subject: Re: 4gb address space limitation for i386 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 31 Aug 2007 04:54:55 -0000 User Bobby wrote: > Ok thank you all for your replies. > > I'm thinking I can't use amd64 on a PIII, right? > > So, given that I'm stuck with this particular piece of hardware, my > only real option is to begin down the long and scary road of PAE. Yes? > > Bob > > On Thu, 30 Aug 2007, youshi10@u.washington.edu wrote: > >> On Thu, 30 Aug 2007, User Bobby wrote: >> >>> I have an IBM xSeries 350 4xPIII with 5.5gb of RAM, and see that >>> only about 3.5gb is being used under the i386 port. I've been >>> looking through the >>> archives to try and figure out what the root of the problem is and I >>> amn't >>> quite sure I know which part of the situation is the real problem. >>> >>> Is it a limitation of the i386 port? That is to say, if there were >>> a specific PIII (i686?) port, would this problem be overcome? Or is >>> it a hardware limitation? Is it necessary to use a not-clean method >>> to access the extra address space (is this what PAE is?), and >>> there's no clean >>> way around it, regardless of the port? >>> >>> I was looking at building a PAE kernel, but was discouraged by the >>> lack of usb and certain SCSI support, both of which I'd really like >>> to have (in the case of SCSI, need to have). Is this lack of >>> support because of an inherent difficulty in the hardware, or could >>> it be overcome in a stable way with modification of the device >>> driver code? >>> >>> My basic (and very hypothetical) question - if I had unlimited time >>> and knowledge (I have limited both), what direction would I take to >>> get access to all 5.5gb of RAM on this particular computer? >>> >>> Thank you, >>> Bob >> >> It's a limitation of the basic i386 architecture; you have to use >> i386 with PAE, or better yet use amd64, because those architectures >> support memory address sizes beyond 32-bits. >> >> Cheers, >> -Garrett Correct. -Garrett