From owner-freebsd-hackers@FreeBSD.ORG Tue Oct 16 10:47:35 2007 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 082E116A469 for ; Tue, 16 Oct 2007 10:47:35 +0000 (UTC) (envelope-from des@des.no) Received: from tim.des.no (tim.des.no [194.63.250.121]) by mx1.freebsd.org (Postfix) with ESMTP id CB64713C461 for ; Tue, 16 Oct 2007 10:47:34 +0000 (UTC) (envelope-from des@des.no) Received: from tim.des.no (localhost [127.0.0.1]) by spam.des.no (Postfix) with ESMTP id DF2E02094; Tue, 16 Oct 2007 12:47:25 +0200 (CEST) X-Spam-Tests: AWL X-Spam-Learn: disabled X-Spam-Score: -0.0/3.0 X-Spam-Checker-Version: SpamAssassin 3.2.3 (2007-08-08) on tim.des.no Received: from ds4.des.no (des.no [80.203.243.180]) by smtp.des.no (Postfix) with ESMTP id C5E5B2088; Tue, 16 Oct 2007 12:47:25 +0200 (CEST) Received: by ds4.des.no (Postfix, from userid 1001) id A44E384488; Tue, 16 Oct 2007 12:47:25 +0200 (CEST) From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= To: Alexander Motin References: <1192209799.00813194.1192199401@10.7.7.3> <1192213457.00813222.1192203001@10.7.7.3> <1192242238.00813408.1192231802@10.7.7.3> <1192289079.00813583.1192278003@10.7.7.3> <4711D237.30808@FreeBSD.org> Date: Tue, 16 Oct 2007 12:47:25 +0200 In-Reply-To: <4711D237.30808@FreeBSD.org> (Alexander Motin's message of "Sun\, 14 Oct 2007 11\:24\:23 +0300") Message-ID: <86zlyj5oaq.fsf@ds4.des.no> User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/22.1 (berkeley-unix) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: freebsd-hackers@freebsd.org Subject: Re: Video memory as swap under FreeBSD X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 16 Oct 2007 10:47:35 -0000 Alexander Motin writes: > Dag-Erling Sm=C3=B8rgrav writes: > > Arne Schwabe writes: > > > Video RAM may also not be as stable as your main RAM. I mean > > > nobody [cares] if a bit flips in video ram. > > That may have been true fifteen years ago, but not today. > Have the anybody ever seen ECC video RAM? Video RAM usually works on > higher frequencies then main RAM and IMHO it must affect stability. > For video RAM some percent of errors is really less important, I have > seen it myself with my previous video card until it died completely. A modern video adapter is basically a processor with a specialized instruction set and multiple parallel pipelines. Video memory is not just a frame buffer, it contains code and structured data (textures, polygon lists etc.) If you're lucky, a single-bit error might just change the color of a pixel, but it might also crash the GPU. DES --=20 Dag-Erling Sm=C3=B8rgrav - des@des.no