From owner-freebsd-arch Mon Sep 11 22:57:52 2000 Delivered-To: freebsd-arch@freebsd.org Received: from cs.waikato.ac.nz (taupo.cs.waikato.ac.nz [130.217.248.134]) by hub.freebsd.org (Postfix) with ESMTP id CDB5037B424 for ; Mon, 11 Sep 2000 22:57:48 -0700 (PDT) Received: (from joerg@localhost) by cs.waikato.ac.nz (8.9.3/8.9.3) id RAA70181; Tue, 12 Sep 2000 17:57:25 +1200 (NZST) (envelope-from joerg) Date: Tue, 12 Sep 2000 17:57:25 +1200 From: Joerg Micheel To: John Baldwin Cc: Greg Lehey , Chuck Paterson , Jason Evans , arch@freebsd.org, joerg@cs.waikato.ac.nz Subject: Re: Long-term mutex ownership (was Re: Interruptable mutex aquires.) Message-ID: <20000912175725.A70000@cs.waikato.ac.nz> References: <20000912143855.O88615@wantadilla.lemis.com> <200009120515.WAA78736@pike.osd.bsdi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200009120515.WAA78736@pike.osd.bsdi.com>; from jhb@pike.osd.bsdi.com on Mon, Sep 11, 2000 at 10:15:25PM -0700 Organization: Dept of Computer Science, University of Waikato, Hamilton, New Zealand Project: WAND - Waikato Applied Network Dynamics, DAG Operating-System: ... powered by FreeBSD Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Mon, Sep 11, 2000 at 10:15:25PM -0700, John Baldwin wrote: > Greg Lehey wrote: > > The general consensus (which I currently don't yet share) is that we > > should use condition variables for things like async event waits. I'm > > still looking for a consistent definition of condition variables, and > > how they differ from "mutexes". > > Go grab Andrew S. Tannebaum's (sp?) _Modern_Operating_Systems_. One of > the first chapters gives execellent treatment to comparing/contrasting > mutexes, semaphores, condition variables, and sleep/wakeup. ... and once you are done with it find out that it is all the same just offering different views onto something that can be implemented and used in exactly the same way. I've just gone through this - trying to explain it to 239 second years students - I can't see any difference. Joerg -- Joerg B. Micheel Email: Waikato Applied Network Dynamics Phone: +64 7 8384794 The University of Waikato, CompScience Fax: +64 7 8585095 Private Bag 3105 Pager: +64 868 38222 Hamilton, New Zealand Plan: TINE and the DAG's To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message