From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 15213 invoked by alias); 15 Feb 2011 02:43:16 -0000 Received: (qmail 15178 invoked by uid 22791); 15 Feb 2011 02:43:15 -0000 X-SWARE-Spam-Status: No, hits=-1.9 required=5.0 tests=AWL,BAYES_00,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from smtp2.caviumnetworks.com (HELO smtp2.caviumnetworks.com) (209.113.159.134) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 15 Feb 2011 02:43:10 +0000 Received: from caexch01.caveonetworks.com (Not Verified[192.168.16.9]) by smtp2.caviumnetworks.com with MailMarshal (v6,7,2,8378) id ; Mon, 14 Feb 2011 21:43:15 -0500 Received: from caexch01.caveonetworks.com ([192.168.16.9]) by caexch01.caveonetworks.com with Microsoft SMTPSVC(6.0.3790.4675); Mon, 14 Feb 2011 18:43:07 -0800 Received: from dd1.caveonetworks.com ([12.108.191.236]) by caexch01.caveonetworks.com over TLS secured channel with Microsoft SMTPSVC(6.0.3790.4675); Mon, 14 Feb 2011 18:43:07 -0800 Message-ID: <4D59E836.1060803@caviumnetworks.com> Date: Tue, 15 Feb 2011 02:43:00 -0000 From: David Daney User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.15) Gecko/20101027 Fedora/3.0.10-1.fc12 Thunderbird/3.0.10 MIME-Version: 1.0 To: Matt Thomas CC: GCC , binutils , Prasun Kapoor Subject: Re: RFC: A new MIPS64 ABI References: <4D5990A4.2050308@caviumnetworks.com> <139B199E-0408-4F99-878C-D7063D607497@dell.com> <20110215021446.GE29824@synopsys.com> <4D59E44F.6010807@caviumnetworks.com> <84F21E9B-D512-40CD-97C3-29CABF7E42B6@3am-software.com> In-Reply-To: <84F21E9B-D512-40CD-97C3-29CABF7E42B6@3am-software.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes Mailing-List: contact binutils-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: binutils-owner@sourceware.org X-SW-Source: 2011-02/txt/msg00156.txt.bz2 On 02/14/2011 06:34 PM, Matt Thomas wrote: > > On Feb 14, 2011, at 6:26 PM, David Daney wrote: > >> On 02/14/2011 06:14 PM, Joe Buck wrote: >>> On Mon, Feb 14, 2011 at 05:57:13PM -0800, Paul Koning wrote: >>>> It seems that this proposal would benefit programs that need more than 2 GB but less than 4 GB, and for some reason really don't want 64 bit pointers. >>>> >>>> This seems like a microscopically small market segment. I can't see any sense in such an effort. >>> >>> I remember the RHEL hugemem patch being a big deal for lots of their >>> customers, so a process could address the full 4GB instead of only 3GB >>> on a 32-bit machine. If I recall correctly, upstream didn't want it >>> (get a 64-bit machine!) but lots of paying customers clamored for it. >>> >>> (I personally don't have an opinion on whether it's worth bothering with). >>> >> >> Also look at the new x86_64 ABI (See all those X32 psABI messages) that the Intel folks are actively working on. This proposal is very similar to what they are doing. > > untrue. N32 is closer to the X32 ABI since it is limited to 2GB. > It would only be 'untrue' if I had said it was *exactly like* the X32 thing. Really n32 is, as you note, already quite similar to what X32 is trying to do. My proposal is really for a small improvement to n32 to allow doubling the size of the virtual address space to 4GB. David Daney