From owner-freebsd-hackers@FreeBSD.ORG Mon Jan 31 14:41:42 2005 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6E60B16A4CE for ; Mon, 31 Jan 2005 14:41:42 +0000 (GMT) Received: from mail.revolutionsp.com (ganymede.revolutionsp.com [64.246.0.2]) by mx1.FreeBSD.org (Postfix) with ESMTP id 219C243D2D for ; Mon, 31 Jan 2005 14:41:42 +0000 (GMT) (envelope-from security@revolutionsp.com) Received: from mail.revolutionsp.com (localhost [127.0.0.1]) by mail.revolutionsp.com (Postfix) with ESMTP id 2E44815C96 for ; Mon, 31 Jan 2005 08:41:34 -0600 (CST) Received: from 81.84.175.77 (SquirrelMail authenticated user security@revolutionsp.com); by mail.revolutionsp.com with HTTP; Mon, 31 Jan 2005 08:41:34 -0600 (CST) Message-ID: <51547.81.84.175.77.1107182494.squirrel@81.84.175.77> Date: Mon, 31 Jan 2005 08:41:34 -0600 (CST) From: security@revolutionsp.com To: freebsd-hackers@freebsd.org User-Agent: SquirrelMail/1.4.3a X-Mailer: SquirrelMail/1.4.3a MIME-Version: 1.0 Content-Type: text/plain;charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Priority: 3 (Normal) Importance: Normal Subject: Simple question about CPUs and processes X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 31 Jan 2005 14:41:42 -0000 Hi list, I'd like some insight on the following; Me and a friend were discussing tech stuff and he said that, when using dual (or more) CPU systems, it is the hardware itself (and alone) choosing which CPU will execute this or that process. But I think it is the OS kernel (FreeBSD in this case) and the SMP implementation that decide this process should live in CPU0 or CPU1, ie it's FreeBSD itself choosing on what CPU a process will reside in. I'm by no means an experienced programmer, so I can't check this for myself; just following logic and intuition, I think it makes sense it is the OS keeping track of what process is in which CPU. Which approach is right? Please add as many technical details as needed.