From owner-freebsd-questions Wed Mar 22 17:54:40 2000 Delivered-To: freebsd-questions@freebsd.org Received: from mail.rdc1.va.home.com (ha1.rdc1.va.home.com [24.2.32.66]) by hub.freebsd.org (Postfix) with ESMTP id 5BE1237B96E for ; Wed, 22 Mar 2000 17:54:38 -0800 (PST) (envelope-from jgowdy@home.com) Received: from cx443070a ([24.4.93.90]) by mail.rdc1.va.home.com (InterMail v4.01.01.00 201-229-111) with SMTP id <20000323015001.HLXY12441.mail.rdc1.va.home.com@cx443070a>; Wed, 22 Mar 2000 17:50:01 -0800 Message-ID: <000f01bf946b$5ae2fca0$0100000a@vista1.sdca.home.com> From: "Jeremiah Gowdy" To: "James" , References: Subject: Re: SMP specifics.......????????? Date: Wed, 22 Mar 2000 17:58:58 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.00.2919.6700 X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6600 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > Does the SMP support allow a process running on each CPU to talk to a single > device with locking the kernel up? It should act the same way as if two processes accessed the device at the same time. Shouldn't lock anything up. >Is it true SMP, or just a little more > processing power? How could it not be true SMP ? What would qualify as just a little more processing power ? The only way I could see it being implemented, on any system, not just FreeBSD, is that the task scheduler runs two processes at once, one on each processor. That's the only way a second processor would add any more processing power. A priority queue with two places for output/processing rather than one. I can't really think of a cheezy way to do it that wouldn't qualify as SMP. Now, I know SMP has other features, like processor affinity and whatnot, of which I'm not familiar, which would be a better implementation. However, even the crappiest implementation of SMP is still "true SMP". As for FreeBSD's SMP, I've not seen any specifics on the implemenatation, except that I hear 4.0 includes linux/processor threads, which allows a multithreaded program's threads to use either processor, allowing a single highly active multithreaded process to use the SMP setup. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message