From owner-freebsd-fs@FreeBSD.ORG Mon Sep 19 19:49:01 2011 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id DCCE2106564A for ; Mon, 19 Sep 2011 19:49:01 +0000 (UTC) (envelope-from fullermd@over-yonder.net) Received: from thyme.infocus-llc.com (server.infocus-llc.com [206.156.254.44]) by mx1.freebsd.org (Postfix) with ESMTP id 851A48FC14 for ; Mon, 19 Sep 2011 19:49:01 +0000 (UTC) Received: from draco.over-yonder.net (c-174-50-4-38.hsd1.ms.comcast.net [174.50.4.38]) (using TLSv1 with cipher ADH-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by thyme.infocus-llc.com (Postfix) with ESMTPSA id EC5C637B495; Mon, 19 Sep 2011 14:32:34 -0500 (CDT) Received: by draco.over-yonder.net (Postfix, from userid 100) id 3233E1787D; Mon, 19 Sep 2011 14:32:34 -0500 (CDT) Date: Mon, 19 Sep 2011 14:32:34 -0500 From: "Matthew D. Fuller" To: Rich Message-ID: <20110919193234.GY14862@over-yonder.net> References: <1316459502.23423.YahooMailClassic@web121212.mail.ne1.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Editor: vi X-OS: FreeBSD User-Agent: Mutt/1.5.21-fullermd.4 (2010-09-15) X-Virus-Scanned: clamav-milter 0.97.2 at thyme.infocus-llc.com X-Virus-Status: Clean Cc: Jason Usher , freebsd-fs@freebsd.org Subject: Re: ZFS obn FreeBSD hardware model for 48 or 96 sata3 paths... X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 19 Sep 2011 19:49:01 -0000 On Mon, Sep 19, 2011 at 03:15:01PM -0400 I heard the voice of Rich, and lo! it spake thus: > > You are assuming you can find such a motherboard. > > I would not make that assumption at this time. And of course it's not enough to get that many lanes to the northbridge (which you aren't gonna get anyway). You have to have that much bandwidth to the CPU package (which you aren't gonna get even if you get that far; the 57GB/s calculated earlier is well over what the highest speed HyperTransport of QPI can pass, much less the links you'll find in real boards). And then you need to have that much bandwidth out to memory (which you also won't get even if you get all the former; triple channel DDR3-1833 falls short). There's something to be said for absurd overspec'ing to avoid having to think too carefully about each piece. But it relies on the absurd not being absurdly absurd (which this is) as well as being realizable (which this isn't). -- Matthew Fuller (MF4839) | fullermd@over-yonder.net Systems/Network Administrator | http://www.over-yonder.net/~fullermd/ On the Internet, nobody can hear you scream.