From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (from majordomo@localhost) by pauillac.inria.fr (8.7.6/8.7.3) id OAA20377; Sun, 11 Apr 2004 14:01:40 +0200 (MET DST) X-Authentication-Warning: pauillac.inria.fr: majordomo set sender to owner-caml-list@pauillac.inria.fr using -f Received: from nez-perce.inria.fr (nez-perce.inria.fr [192.93.2.78]) by pauillac.inria.fr (8.7.6/8.7.3) with ESMTP id OAA20397 for ; Sun, 11 Apr 2004 14:01:39 +0200 (MET DST) Received: from ptb-relay02.plus.net (ptb-relay02.plus.net [212.159.14.213]) by nez-perce.inria.fr (8.12.10/8.12.10) with ESMTP id i3BC2ajq014390 for ; Sun, 11 Apr 2004 14:02:36 +0200 Received: from [80.229.56.224] (helo=chetara) by ptb-relay02.plus.net with esmtp (Exim) id 1BCdeb-000L4M-4V for caml-list@inria.fr; Sun, 11 Apr 2004 12:01:37 +0000 From: Jon Harrop Organization: University of Cambridge To: caml-list@inria.fr Subject: Re: [Caml-list] OpenGL Date: Sun, 11 Apr 2004 13:01:34 +0100 User-Agent: KMail/1.5.4 References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200404111301.34781.jdh30@cam.ac.uk> X-Miltered: at nez-perce by Joe's j-chkmail ("http://j-chkmail.ensmp.fr")! X-Loop: caml-list@inria.fr X-Spam: no; 0.00; caml-list:01 2004:99 pauses:01 wether:01 vertices:01 api:01 vastly:01 slower:01 ocaml:01 ocaml:01 garbage:01 opengl:02 orders:97 computations:03 overhead:03 Sender: owner-caml-list@pauillac.inria.fr Precedence: bulk X-Keywords: X-UID: 251 On Sunday 11 April 2004 7:20 am, Brian Hurt wrote: > ... > second, or 1 frame every 16.6ms, a 20ms pause to garbage collect is bad. > This is soft realtime, but it's still realtime programming. And I have > reliable reports of people seeing 500ms pauses in Java programs. > > Wether this would be a problem for Ocaml or not I can't speak to. Well, I'm writing real-time graphical programs in ocaml and, so far, I haven't had any problems with the GC. At one point I thought I had a serious problem with it, but it turned out that increasing the number of vertices in a display list over an unknown (to me, at least) theshold was resulting in a 4 orders of magnitude drop in performance in the GL, nothing to do with ocaml or its GC. > ... > Notice how I phrased my response. Especially since currently the vast > majority of heavy computation is done on the graphics card, I'd expect the > overhead of the API to be lost in the noise. Although the "vast majority of heavy computation" may be done on the graphics card, don't forget that the relatively easy computations done on the vastly slower CPU in serial are just as responsible for the overall speed. Cheers, Jon. ------------------- To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ Beginner's list: http://groups.yahoo.com/group/ocaml_beginners