From owner-freebsd-arch Thu Jun 27 21:54: 3 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 A66F337B405 for ; Thu, 27 Jun 2002 21:53:45 -0700 (PDT) Received: from apollo.backplane.com (apollo.backplane.com [216.240.41.2]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3159443E09 for ; Thu, 27 Jun 2002 21:53:45 -0700 (PDT) (envelope-from dillon@apollo.backplane.com) Received: from apollo.backplane.com (localhost [127.0.0.1]) by apollo.backplane.com (8.12.4/8.12.3) with ESMTP id g5S4riT4002879; Thu, 27 Jun 2002 21:53:44 -0700 (PDT) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.12.4/8.12.3/Submit) id g5S4rioB002878; Thu, 27 Jun 2002 21:53:44 -0700 (PDT) (envelope-from dillon) Date: Thu, 27 Jun 2002 21:53:44 -0700 (PDT) From: Matthew Dillon Message-Id: <200206280453.g5S4rioB002878@apollo.backplane.com> To: nerd@xyz.com Cc: "Gary Thorpe" , arch@FreeBSD.ORG Subject: Re: Larry McVoy's slides on cache coherent clusters References: <200206280035.g5S0ZJmP098253@www.xyz.com> 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 : :In another email on the same thread, Matt Dillon wrote: : :>NUMA then becomes just another, faster transport mechanism. That is :>the direction I believe the BSDs will take... transparent clustering :>with NUMA transport, network transport, or a hybrid of both. : :Matt: If you don't have a single memory immage you don't have NUMA. :If you do have it then the transport mechanism will be saturated just :moving "RAM" around and will not be available for network, I/O or :whatever else. : :-michael : :michael at michael dot galassi dot org Well, I wasn't trying to intimate that programs could migrate willy nilly across the cluster. I was just saying that NUMA is roughly equivalent to clustering in terms of deterministic program and OS design (basically what you said about never migrating outside of a quad), so its better to design an OS or an application to run well in a clustered environment, which covers NUMA, rather then just a NUMA environment. My opinion in regards to clustering closely matches what you said. I am heavily into peer-to-peer quorum-write based infrastructure designs that can survive machines going on and off line willy nilly in a cluster without glitching the 'application' running on top of the infrastructure. I still intend to get the database technology I developed at Backplane Inc (which is exactly the above) into the open-source world. In anycase, I have great respect for Sequent. When I was at Berkeley working on Postgres we had a (I think) 16 processor (486 based) sequent and it blew away everything else the university had at the time. The only thing that ran 'slow' was the final link line in the build :-) -Matt Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message