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=AWL autolearn=disabled version=3.1.3 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 8A8C6BC69 for ; Tue, 4 Dec 2007 15:37:17 +0100 (CET) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AgAAANr0VEc+BBBmg2dsb2JhbACBW41zAQEIAggn X-IronPort-AV: E=Sophos;i="4.23,248,1194217200"; d="scan'208";a="19968731" Received: from smtp-102-tuesday.nerim.net (HELO kraid.nerim.net) ([62.4.16.102]) by mail4-smtp-sop.national.inria.fr with ESMTP; 04 Dec 2007 15:37:17 +0100 Received: from hector.lesours (ours.starynkevitch.net [213.41.244.95]) by kraid.nerim.net (Postfix) with ESMTP id 52315CF182; Tue, 4 Dec 2007 15:37:16 +0100 (CET) Received: from [192.168.0.1] (glinka.lesours [192.168.0.1]) by hector.lesours (Postfix) with ESMTP id D658020F18D; Tue, 4 Dec 2007 15:34:29 +0100 (CET) Message-ID: <47556617.7020602@starynkevitch.net> Date: Tue, 04 Dec 2007 15:37:11 +0100 From: Basile STARYNKEVITCH User-Agent: Mozilla-Thunderbird 2.0.0.6 (X11/20071008) MIME-Version: 1.0 To: Christophe Raffalli Cc: caml-list@yquem.inria.fr Subject: Re: [Caml-list] minithread (was OCaml on Sony PS3) References: <875c7e070709060755r1d0d099ds30a25ea78d0fd85a@mail.gmail.com> <46E01A27.1070207@janestcapital.com> <509223F0BF55E74FA1247D17207E7A0C01D75893@orsmsx419.amr.corp.intel.com> <87r6lb90tw.fsf@linux-france.org> <46E046DF.5010103@univ-savoie.fr> <46E04B85.1020004@naughtydog.com> <13858952.post@talk.nabble.com> <47528593.9060106@inria.fr> <14116972.post@talk.nabble.com> <200712021419.01821.konrad@tylerc.org> <14121946.post@talk.nabble.com> <4754643A.6020503@univ-savoie.fr> In-Reply-To: <4754643A.6020503@univ-savoie.fr> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam: no; 0.00; basile:01 basile:01 ocaml:01 christophe:01 raffalli:01 ocaml:01 powerpc:01 doable:01 damien:01 ocamlopt:01 damien:01 faiencerie:01 92340:01 reine:01 sony:98 Christophe Raffalli wrote: > I propose the following idea for OCaml on Cell PowerPC or multicore > machine (this is just an idea, > there ay be a lot of thing I did not see ... in other word there is > probably a lot of work to do, but may be not too much): > > - Create two functions and one data type to start "mini-thread": As David MENTRE explained, this is not very realistic. However, (one of the) the CELL coprocessor -eg SPU) might be used to implemented Ocaml garbage collector. A copying GC has to move quite a lot of data, and it could be possible that CELL's coprocessors could be useful for that (assuming that they access memory as quickly as the processor). I don't know if Gallium has resources for that (I suppose not, except perhaps maybe for an internship?), and I have no idea if it is easily doable or nearly impossible (maybe the current SPU limitations -in particular code size- are too strong). Anyway, it might not help that much performance on Cells systems (eg PS3) because the GC is probably at most eating less than half of the resources (Damien & Xavier told me recently that the GC is usually using less than 20% of CPU, the KnuthBendix test case on ocamlopt being unusual to eat about a third of the CPU time). The Ocaml GC is quite good (a big bravo to Damien Doligez & Xavier Leroy). I still think that SPU on PS3 are only useful for games, or specialized (e.g. graphical) applications. -- Basile STARYNKEVITCH http://starynkevitch.net/Basile/ email: basilestarynkevitchnet mobile: +33 6 8501 2359 8, rue de la Faiencerie, 92340 Bourg La Reine, France *** opinions {are only mines, sont seulement les miennes} ***