From owner-freebsd-alpha Thu Oct 5 14:26:24 2000 Delivered-To: freebsd-alpha@freebsd.org Received: from post.mail.nl.demon.net (post-10.mail.nl.demon.net [194.159.73.20]) by hub.freebsd.org (Postfix) with ESMTP id DFBB237B503 for ; Thu, 5 Oct 2000 14:26:18 -0700 (PDT) Received: from [212.238.54.101] (helo=freebie.demon.nl) by post.mail.nl.demon.net with smtp (Exim 3.14 #2) id 13hIWv-0004aH-00; Thu, 05 Oct 2000 21:26:17 +0000 Received: (from wkb@localhost) by freebie.demon.nl (8.11.0/8.11.0) id e95LS5407182; Thu, 5 Oct 2000 23:28:05 +0200 (CEST) (envelope-from wkb) Date: Thu, 5 Oct 2000 23:28:05 +0200 From: Wilko Bulte To: Doug Rabson Cc: Matthew Jacob , FreeBSD-alpha mailing list Subject: Re: max memory on Alpha? Message-ID: <20001005232805.B7134@freebie.demon.nl> References: <20001003212847.A1868@freebie.demon.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2i In-Reply-To: ; from dfr@nlsystems.com on Wed, Oct 04, 2000 at 11:46:29PM +0100 X-OS: FreeBSD 4.1-STABLE X-PGP: finger wilko@freebsd.org Sender: owner-freebsd-alpha@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Wed, Oct 04, 2000 at 11:46:29PM +0100, Doug Rabson wrote: > 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. From looking at the code it would be instructive to compile a kernel with DEBUG_CLUSTER and see what is says (hopefully before panicing ;-) I need a sensible -current built first (my -current disk that I carry around from machine to machine is a bit whacko). Hmm, or maybe -stable is easier.. Will see what I can do. W/ -- Wilko Bulte wilko@freebsd.org Arnhem, the Netherlands To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message