From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on yquem.inria.fr X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=none autolearn=disabled version=3.1.3 X-Original-To: caml-list@yquem.inria.fr Delivered-To: caml-list@yquem.inria.fr Received: from mail4-relais-sop.national.inria.fr (mail4-relais-sop.national.inria.fr [192.134.164.105]) by yquem.inria.fr (Postfix) with ESMTP id BF49DBBAF for ; Thu, 10 Jul 2008 21:16:33 +0200 (CEST) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AsgCAEj9dUjU436zgWdsb2JhbACBWpBLAQEQIAOfMwE X-IronPort-AV: E=Sophos;i="4.30,339,1212357600"; d="scan'208";a="27214400" Received: from moutng.kundenserver.de ([212.227.126.179]) by mail4-smtp-sop.national.inria.fr with ESMTP; 10 Jul 2008 21:16:33 +0200 Received: from gate.lan.gerd-stolpmann.de (dslb-088-068-196-079.pools.arcor-ip.net [88.68.196.79]) by mrelayeu.kundenserver.de (node=mrelayeu1) with ESMTP (Nemesis) id 0MKwpI-1KH1cT1Du3-0001iU; Thu, 10 Jul 2008 21:15:57 +0200 Received: from [192.168.0.32] (fw.lan.gerd-stolpmann.de [192.168.1.1]) by gate.lan.gerd-stolpmann.de (Postfix) with ESMTP id D9E22C077; Thu, 10 Jul 2008 21:15:56 +0200 (CEST) Subject: Re: [Caml-list] thousands of CPU cores From: Gerd Stolpmann To: J C Cc: caml-list@yquem.inria.fr In-Reply-To: References: Content-Type: text/plain Date: Thu, 10 Jul 2008 21:15:56 +0200 Message-Id: <1215717356.24773.17.camel@flake.lan.gerd-stolpmann.de> Mime-Version: 1.0 X-Mailer: Evolution 2.12.1 Content-Transfer-Encoding: 7bit X-Provags-ID: V01U2FsdGVkX1+bUcS6WVNr/oIki5v+YphbNmwZI7wAHz2Mppu o2stFPJEtu6k0kAMdhe+Yldmstv+elgIr6lPbZk/tJB+q3nAJp 71dmFhBj1XtU05ih567dHODTPkjyYdk X-Spam: no; 0.00; gerd:01 stolpmann:01 haskell:01 ocaml:01 ocaml:01 gerd:01 stolpmann:01 viktoriastr:01 64293:01 darmstadt:01 6151:01 6151:01 cnet:98 propaganda:98 ...,:98 Am Mittwoch, den 09.07.2008, 22:57 -0700 schrieb J C: > I know that Caml team wanted to see if many-core shared-memory systems > were going to stick around before bothering with Caml development that > takes advantage of them. > > Well, it looks like they are here to stay, after all: > > http://news.cnet.com/8301-13924_3-9981760-64.html > > As much as I hate to look a gift horse in the mouth, and I think Caml > has been a great and grossly underappreciated product, I need to see > if writing Caml is a viable code investment for the coming years or > something like Haskell, SML, F# or even Ada will be a better long-term > alternative. > > Are there plans to make Caml threads OS-native threads, or add > OpenMP-style primitives, or otherwise support multiple CPU cores? And > if so, roughly in what time frame? I wouldn't take this article too seriously. It's just speculation. Actually, the whole multi-core technology is a challenge for software development. You cannot simply take a program that runs well on 4 cores and expect that it scales up to 400. Software must be designed from grounds up differently for such architectures. Just open up your mind to this perspective: It's a big risk for the CPU vendors to haven taken the direction to multi-core. Except for some standard components and some specially-adapted programs multi-core is more or less not exploited today. So these vendors are trying to push the software developers into this direction, and hope they find new ideas for designing multi-core-capable programs. This article is just propaganda for this hidden agenda. It can also happen that multi-core with too many cores turns out as failure - in the sense that the mass market is not ready for it. In Ocaml you can exploit multi-core currently only by using multi-processing parallel programs that communicate over message passing (and only on Unix). Actually, it's an excellent language for this style. I've written (with some other guys) a big distributed system using Ocamlnet's netplex and sunrpc libraries (actually, a search engine..., http://wink.com). Ocaml is an excellent choice because you can quickly develop working programs that run 24/7. In the distributed world stability is quite important. For a quick introduction to the technology I'm talking about, see my blog article here: http://blog.camlcity.org/blog/parallelmm.html Gerd -- ------------------------------------------------------------ Gerd Stolpmann * Viktoriastr. 45 * 64293 Darmstadt * Germany gerd@gerd-stolpmann.de http://www.gerd-stolpmann.de Phone: +49-6151-153855 Fax: +49-6151-997714 ------------------------------------------------------------