From owner-freebsd-arch Tue Oct 15 8:52:31 2002 Delivered-To: freebsd-arch@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id D78FA37B401 for ; Tue, 15 Oct 2002 08:52:29 -0700 (PDT) Received: from duke.cs.duke.edu (duke.cs.duke.edu [152.3.140.1]) by mx1.FreeBSD.org (Postfix) with ESMTP id E2AEE43EAA for ; Tue, 15 Oct 2002 08:52:28 -0700 (PDT) (envelope-from gallatin@cs.duke.edu) Received: from grasshopper.cs.duke.edu (grasshopper.cs.duke.edu [152.3.145.30]) by duke.cs.duke.edu (8.9.3/8.9.3) with ESMTP id LAA04413; Tue, 15 Oct 2002 11:52:28 -0400 (EDT) Received: (from gallatin@localhost) by grasshopper.cs.duke.edu (8.11.6/8.9.1) id g9FFpw655630; Tue, 15 Oct 2002 11:51:58 -0400 (EDT) (envelope-from gallatin@cs.duke.edu) From: Andrew Gallatin MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15788.14750.474882.99633@grasshopper.cs.duke.edu> Date: Tue, 15 Oct 2002 11:51:58 -0400 (EDT) To: Peter Wemm Cc: arch@FreeBSD.org Subject: Re: Database indexes and ram In-Reply-To: <20021015011435.763AE2A88D@canning.wemm.org> References: <3DAA695F.96E345E6@mindspring.com> <20021015011435.763AE2A88D@canning.wemm.org> X-Mailer: VM 6.75 under 21.1 (patch 12) "Channel Islands" XEmacs Lucid Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Peter Wemm writes: > Terry Lambert wrote: > > Peter Wemm wrote: > > > And then there's the AGP remap table stuff to provide a window from > > > anywhere in memory into the lower 4G of space that's within reach of 32 bit > > > PCI devices... > > > > Peter, you are sneaky... in a good way. > > > > Do you really think this could be abused this way? How much, in the > > way of windows, can you have lying around at one time? I'm not very > > AGP-aware, other than "I need it for my X server". > > I cant claim credit for this.. The linux folks supposedly have it working - > David O'Brien told me about it. > FWIW, Doug Rabson thought of this a few years ago when we first ported FreeBSD/alpha to the API UP1x000. Unlike most alphas, it has an AGP slot, and it does not have a pci chipset capable of doing scatter/gather dma mapping. Doug suggested that I use the AGP remap table for ISA dma, but I could never make it work. I ended up just doing bounce buffers. Drew To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message