From owner-freebsd-smp Sun Apr 27 19:24:33 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.5/8.8.5) id TAA13616 for smp-outgoing; Sun, 27 Apr 1997 19:24:33 -0700 (PDT) Received: from cais.cais.com (root@cais.com [199.0.216.4]) by hub.freebsd.org (8.8.5/8.8.5) with ESMTP id TAA13610 for ; Sun, 27 Apr 1997 19:24:31 -0700 (PDT) Received: from earth.mat.net (root@earth.mat.net [205.252.122.1]) by cais.cais.com (8.8.5/8.7.3) with SMTP id WAA25442 for ; Sun, 27 Apr 1997 22:24:23 -0400 (EDT) Received: from Journey2.mat.net (journey2.mat.net [205.252.122.116]) by earth.mat.net (8.6.12/8.6.12) with SMTP id WAA03754 for ; Sun, 27 Apr 1997 22:24:21 -0400 Date: Sun, 27 Apr 1997 22:23:45 -0400 (EDT) From: Chuck Robey To: FreeBSD-SMP@FreeBSD.org Subject: SMP Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-smp@FreeBSD.org X-Loop: FreeBSD.org Precedence: bulk I am in the throes of writing an OS for an OS class. This is a class project, and not ever going to be made public, but it got me thinking about smp. Specifically, I'm wondering how kernel stuff works with 2 processors .... are there two copies of the kernel running? Or does one processor have to interrupt the other to get the kernel stuff working? I'm curious about that, and about how mutual exclusion type things work when there're two processors that could be doing top level things at once. How are things like virtual memory handled? Do the two processors have to cooperate on VM? How about FS stuff ... are the two processors having ghe same view of the disk (especially vnodes?) I'm not looking for a treatise here, but maybe just a few words on the major changes that the smp code does would be really appreciated. Even one long paragraph would better than nothing (I don't have time to read thru all the code now). ----------------------------+----------------------------------------------- Chuck Robey | Interests include any kind of voice or data chuckr@eng.umd.edu | communications topic, C programming, and Unix. 9120 Edmonston Ct #302 | Greenbelt, MD 20770 | I run Journey2 and picnic, both FreeBSD (301) 220-2114 | version 3.0 current -- and great FUN! ----------------------------+-----------------------------------------------