From owner-freebsd-current Thu Sep 18 23:10:41 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id XAA15711 for current-outgoing; Thu, 18 Sep 1997 23:10:41 -0700 (PDT) Received: from dyson.iquest.net (dyson.iquest.net [198.70.144.127]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id XAA15704; Thu, 18 Sep 1997 23:10:34 -0700 (PDT) Received: (from root@localhost) by dyson.iquest.net (8.8.6/8.8.5) id BAA00804; Fri, 19 Sep 1997 01:10:23 -0500 (EST) From: "John S. Dyson" Message-Id: <199709190610.BAA00804@dyson.iquest.net> Subject: Re: FYI: regarding our rfork(2) In-Reply-To: <199709190518.XAA16454@rocky.mt.sri.com> from Nate Williams at "Sep 18, 97 11:18:19 pm" To: nate@mt.sri.com (Nate Williams) Date: Fri, 19 Sep 1997 01:10:23 -0500 (EST) Cc: karpen@ocean.campus.luth.se, dyson@freebsd.org, current@freebsd.org Reply-To: dyson@freebsd.org X-Mailer: ELM [version 2.4ME+ PL31 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@freebsd.org X-Loop: FreeBSD.org Precedence: bulk Nate Williams said: > > We are actually doing a pure memory sharing operation. We will be sharing > > everything, plan 9 doesn't appear to share the stack. In order to support > > pthreads, (and most thread schemes that I have seen), it is best to allow > > full access to all of the thread stacks. > > Forgive me for being naive, but in all of my experiences with threads > (not much, but lots lately with Java), it seems that sharing the stack > is asking for nothing but trouble. If you need to share memory, > allocate a 'global' shared memory bank that everyone can use, and use > it. > I don't disagree with what you are saying, however, we need to be able to have full access to the stacks in every thread. Of course, we would be wise to create guard page(s) between stacks. -- John dyson@freebsd.org jdyson@nc.com