From owner-freebsd-current Sun May 17 14:01:34 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id OAA16149 for freebsd-current-outgoing; Sun, 17 May 1998 14:01:34 -0700 (PDT) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from smtp02.primenet.com (daemon@smtp02.primenet.com [206.165.6.132]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id OAA16131 for ; Sun, 17 May 1998 14:01:24 -0700 (PDT) (envelope-from tlambert@usr05.primenet.com) Received: (from daemon@localhost) by smtp02.primenet.com (8.8.8/8.8.8) id OAA09967; Sun, 17 May 1998 14:00:53 -0700 (MST) Received: from usr05.primenet.com(206.165.6.205) via SMTP by smtp02.primenet.com, id smtpd009924; Sun May 17 14:00:42 1998 Received: (from tlambert@localhost) by usr05.primenet.com (8.8.5/8.8.5) id OAA29938; Sun, 17 May 1998 14:00:39 -0700 (MST) From: Terry Lambert Message-Id: <199805172100.OAA29938@usr05.primenet.com> Subject: Re: cvs commit: src/sys/conf param.c src/sys/kern uipc_domain.c uipc_proto.c uipc_socket.c uipc_socket2.c uipc_usrreq.c src/sys/ To: toor@dyson.iquest.net (John S. Dyson) Date: Sun, 17 May 1998 21:00:38 +0000 (GMT) Cc: tlambert@primenet.com, eivind@yes.no, wollman@khavrinen.lcs.mit.edu, current@FreeBSD.ORG In-Reply-To: <199805162247.RAA05770@dyson.iquest.net> from "John S. Dyson" at May 16, 98 05:47:25 pm X-Mailer: ELM [version 2.4 PL25] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > > The protection you would gain is statistical; there would still be > > failure races if you did it (consider a low memory condition; just > > because you can expand the page mappings doesn't mean that you will > > have pages available for them to point to). > > > > This is why type stable memory is so annoying. 8-). > > You haven't made any arguments for or against type stable memory. Limited > memory size is annoying, but a fact of life. The code can be made to be > dynamic, but the critical region issues become challenging. TSM prevents page migration of the type you would need to have, assuming you don't use a "handle" pointer and/or segment identifier, should you need to expand a region without preallocating a large number of anonymous pages that you could "type-commit" at interrupt time. This isn't really intended to be an argument against TSM (an idea which I support), just a note that it makes some things more annoying to implement. Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message