From owner-freebsd-smp Mon Mar 3 16: 8:37 2003 Delivered-To: freebsd-smp@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8AC1E37B401; Mon, 3 Mar 2003 16:08:36 -0800 (PST) Received: from sccrmhc03.attbi.com (sccrmhc03.attbi.com [204.127.202.63]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8ECCA43F93; Mon, 3 Mar 2003 16:08:35 -0800 (PST) (envelope-from julian@elischer.org) Received: from interjet.elischer.org (12-232-168-4.client.attbi.com[12.232.168.4]) by sccrmhc03.attbi.com (sccrmhc03) with ESMTP id <2003030400083400300aj3tje>; Tue, 4 Mar 2003 00:08:34 +0000 Received: from localhost (localhost.elischer.org [127.0.0.1]) by InterJet.elischer.org (8.9.1a/8.9.1) with ESMTP id QAA44878; Mon, 3 Mar 2003 16:08:32 -0800 (PST) Date: Mon, 3 Mar 2003 16:08:31 -0800 (PST) From: Julian Elischer To: John Baldwin Cc: smp@freebsd.org Subject: RE: UP ans SMP on the same kernel In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Mon, 3 Mar 2003, John Baldwin wrote: > > On 03-Mar-2003 Julian Elischer wrote: > > > > > > How much work would it take to make a kernel that could run > > on both SMP and UP machines (and use the extra CPUs?) > > > > UP kernels can run on SMP hardware, so I guess that it's mainly finding > > a way of switching from using the PIC to using some APICS > > dynamically, when you find that you have SMP hardware. > > > > Incidently I have several UP machines that have APICs > > and it may be effective to be able to run an APIC > > kernel on this hardware.. > > > > (This all assumes that the rest of the kernel was compiled > > SMP to have all the lockeng etc.) > > I am working on this, but it's taking a while amongst other > distractions. The real work is in the PIC vs. APIC stuff. > The actual SMP part is fairly easy as the sparc64, alpha, and > ia64 ports demonstrate. That's good to know.. We have spent a lot of effort making one "universal" kernel for our systems in the field, but now that we have some SMP machines, suddenly we have 2 again. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message