From owner-freebsd-alpha Wed Oct 4 15:46:45 2000 Delivered-To: freebsd-alpha@freebsd.org Received: from anchor-post-31.mail.demon.net (anchor-post-31.mail.demon.net [194.217.242.89]) by hub.freebsd.org (Postfix) with ESMTP id DCF5237B66D for ; Wed, 4 Oct 2000 15:46:41 -0700 (PDT) Received: from nlsys.demon.co.uk ([158.152.125.33] helo=herring.nlsystems.com) by anchor-post-31.mail.demon.net with esmtp (Exim 2.12 #1) id 13gxJ6-000G21-0V; Wed, 4 Oct 2000 23:46:37 +0100 Received: from salmon.nlsystems.com (salmon.nlsystems.com [10.0.0.3]) by herring.nlsystems.com (8.9.3/8.8.8) with ESMTP id XAA14160; Wed, 4 Oct 2000 23:52:58 +0100 (BST) (envelope-from dfr@nlsystems.com) Date: Wed, 4 Oct 2000 23:46:29 +0100 (BST) From: Doug Rabson To: Wilko Bulte Cc: Matthew Jacob , FreeBSD-alpha mailing list Subject: Re: max memory on Alpha? In-Reply-To: <20001003212847.A1868@freebie.demon.nl> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-alpha@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Tue, 3 Oct 2000, Wilko Bulte wrote: > On Tue, Oct 03, 2000 at 11:57:55AM -0700, Matthew Jacob wrote: > > On Tue, 3 Oct 2000, Wilko Bulte wrote: > > > > > What is the currently max supported memory size on Alpha? 2Gb maybe? > > > Or will 4Gb also be OK? > > > > > > Reason for asking is that I want to try a AS8400 who is equipped > > > with 3x 4Gb memory module. > > > > I've run 8400s up to 2GB. Any more than that and you'll find that S/G > > DMA hasn't been finished ;-). > > Well, on 12Gb it panics with pmap_foo off the top of my head> on 4.1-R ;-) Might this mean it cannot create the > necessary page table admin on > 2Gb? > > Do you know *if* there is a hard limit at 2Gb? I don't think there is a *hard* limit for the basic VM system but I imagine it might have problems finding a large enough contiguous region to map the vm_page_t structures. The main limitation is in the i/o system as previously noted. -- Doug Rabson Mail: dfr@nlsystems.com Phone: +44 20 8348 6160 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message