From owner-freebsd-hackers Thu Feb 11 00:50:06 1999 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id AAA14381 for freebsd-hackers-outgoing; Thu, 11 Feb 1999 00:50:06 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from iquest3.iquest.net (iquest3.iquest.net [209.43.20.203]) by hub.freebsd.org (8.8.8/8.8.8) with SMTP id AAA14369 for ; Thu, 11 Feb 1999 00:50:03 -0800 (PST) (envelope-from toor@y.dyson.net) Received: (qmail 26301 invoked from network); 11 Feb 1999 08:50:00 -0000 Received: from dyson.iquest.net (HELO y.dyson.net) (198.70.144.127) by iquest3.iquest.net with SMTP; 11 Feb 1999 08:50:00 -0000 Received: (from root@localhost) by y.dyson.net (8.9.1/8.9.1) id DAA03600; Thu, 11 Feb 1999 03:49:59 -0500 (EST) Message-Id: <199902110849.DAA03600@y.dyson.net> Subject: Re: portability of shm, mmap, pipes and socket IPC In-Reply-To: <199902110625.WAA88612@apollo.backplane.com> from Matthew Dillon at "Feb 10, 99 10:25:29 pm" To: dillon@apollo.backplane.com (Matthew Dillon) Date: Thu, 11 Feb 1999 03:49:59 -0500 (EST) Cc: tlambert@primenet.com, dyson@iquest.net, dg@root.com, kuku@gilberto.physik.RWTH-Aachen.DE, hackers@FreeBSD.ORG From: "John S. Dyson" Reply-To: dyson@iquest.net X-Mailer: ELM [version 2.4ME+ PL38 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Matthew Dillon said: > > The issue of file-backed storage verses anon mmap is certainly real, > but it's divergent enough from the original discussion that it should > have been brought up as a separate item rather then as a response, > That's all. > > This brings up a good point, though... I think it might make sense > to be able to specify a MAP_ flag to mmap to indicate that the file's > dirty data backing the map ( for non-anonymous maps ) does not have to > be synced by the syncer. That would make mmap() a much more useful > tool for sharing working sets. The file data would be synced on the > last close of the vnode and if the program really doesn't want it to be > synced at all, the program could madvise() it free ( and we could fix > madvise() to actually support throw-away on a vnode ). > > Another possibility would be adding a memory reference passing capability > to unix-domain socket messaging. We can already pass descriptors and > access rights, why not memory too? ( ala mach ). > I agree with much of this. I suggest looking at some commerical implementations and/or standards docs to see a good way to implement the above from an API standpoint. -- John | Never try to teach a pig to sing, dyson@iquest.net | it makes one look stupid jdyson@nc.com | and it irritates the pig. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message