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=1.5 required=5.0 tests=AWL,SPF_SOFTFAIL autolearn=disabled version=3.1.3 X-Original-To: caml-list@yquem.inria.fr Delivered-To: caml-list@yquem.inria.fr Received: from mail3-relais-sop.national.inria.fr (mail3-relais-sop.national.inria.fr [192.134.164.104]) by yquem.inria.fr (Postfix) with ESMTP id C1179BBAF for ; Fri, 25 Sep 2009 09:32:39 +0200 (CEST) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Aj0BABAPvErVhjEXkGdsb2JhbACbAQEBAQEJCQwHEwO7HIQcBQ X-IronPort-AV: E=Sophos;i="4.44,450,1249250400"; d="scan'208";a="34955804" Received: from ihsmtp01voda.lis.interhost.com (HELO ihsmtp01cons.lis.interhost.com) ([213.134.49.23]) by mail3-smtp-sop.national.inria.fr with ESMTP; 25 Sep 2009 09:32:39 +0200 Received: from [192.168.1.64] ([77.54.228.130]) by ihsmtp01cons.lis.interhost.com with Microsoft SMTPSVC(6.0.3790.3959); Fri, 25 Sep 2009 08:28:57 +0100 Message-ID: <4ABC720A.7060706@inescporto.pt> Date: Fri, 25 Sep 2009 08:32:26 +0100 From: Hugo Ferreira User-Agent: Thunderbird 2.0.0.23 (X11/20090817) MIME-Version: 1.0 To: caml-list@yquem.inria.fr Subject: Re: [Caml-list] OC4MC : OCaml for Multicore architectures References: <200909241409.56894.jon@ffconsultancy.com> <20090924164933.GA5637@annexia.org> <200909242209.50565.jon@ffconsultancy.com> <20090925.130721.70227045.garrigue@math.nagoya-u.ac.jp> In-Reply-To: <20090925.130721.70227045.garrigue@math.nagoya-u.ac.jp> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 25 Sep 2009 07:28:57.0188 (UTC) FILETIME=[D7C33240:01CA3DB1] X-Spam: no; 0.00; ocaml:01 ocaml:01 speedup:01 speedup:01 bounded:01 wrote:01 tracing:01 caml-list:01 algorithm:01 linear:02 algorithmic:02 commenting:02 garrigue:03 jacques:03 programming:03 Hello, In tried not getting into this discussion but I could not resist commenting on the following: Jacques Garrigue wrote: >... > ... There are applications for that (ray tracing is > one), but this is not the kind of needs most people have. >... As with most technology people will or will not use something according to their perceived effort/pleasure to learn/use something and the advantages it is supposed to bring. Put it another way; if parallel/concurrent programming could be easily used with a minimum of effort then I believe "most people" would use it simply because it is available. In other words the (ready) availability of (multi-core PCs and) parallel computing support (in Ocaml) will certainly influence the number of people that will take advantage of it simply because it is available (confer with e-mails on this thread). >... > If I tell you that you just have to modify a bit your program to get a > near linear speedup, then it looks great. But in practice it is rather > having to rethink completely your algorithm, to eventually get a > speedup bounded by bandwidth, and starting from a point lower than the > original single thread program. >... Rethinking our application/algorithmic structure may not be a real deterrent. An application does not require parallel/concurrent processing everywhere. It is really a question of identifying where and when this is useful. Much like selecting the most "appropriate" data-structure for any application. It's not an all or nothing proposition. My 2 cents. Regards, Hugo F.