From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Original-To: caml-list@sympa.inria.fr Delivered-To: caml-list@sympa.inria.fr Received: from mail3-relais-sop.national.inria.fr (mail3-relais-sop.national.inria.fr [192.134.164.104]) by sympa.inria.fr (Postfix) with ESMTPS id 72DD37F75C for ; Tue, 9 Sep 2014 17:26:28 +0200 (CEST) Received-SPF: None (mail3-smtp-sop.national.inria.fr: no sender authenticity information available from domain of yotambarnoy@gmail.com) identity=pra; client-ip=209.85.192.49; receiver=mail3-smtp-sop.national.inria.fr; envelope-from="yotambarnoy@gmail.com"; x-sender="yotambarnoy@gmail.com"; x-conformance=sidf_compatible Received-SPF: Pass (mail3-smtp-sop.national.inria.fr: domain of yotambarnoy@gmail.com designates 209.85.192.49 as permitted sender) identity=mailfrom; client-ip=209.85.192.49; receiver=mail3-smtp-sop.national.inria.fr; envelope-from="yotambarnoy@gmail.com"; x-sender="yotambarnoy@gmail.com"; x-conformance=sidf_compatible; x-record-type="v=spf1" Received-SPF: None (mail3-smtp-sop.national.inria.fr: no sender authenticity information available from domain of postmaster@mail-qg0-f49.google.com) identity=helo; client-ip=209.85.192.49; receiver=mail3-smtp-sop.national.inria.fr; envelope-from="yotambarnoy@gmail.com"; x-sender="postmaster@mail-qg0-f49.google.com"; x-conformance=sidf_compatible X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AugBAN4bD1TRVcAxlGdsb2JhbABZDoQpBIJ4znsBgQUIFhABAQEBBwsLCRIshAMBAQEDARIRHQEbHQEDAQsGBQQBBg0qAgIhAQERAQUBHAYTIogLAQMJCJp5a4swgXKDEIk0ChknDWaFdwERAQUOjRKCLQeCeYFTAQSPLIs3ghCOc4RJGCmEUF4hLwGCTgEBAQ X-IPAS-Result: AugBAN4bD1TRVcAxlGdsb2JhbABZDoQpBIJ4znsBgQUIFhABAQEBBwsLCRIshAMBAQEDARIRHQEbHQEDAQsGBQQBBg0qAgIhAQERAQUBHAYTIogLAQMJCJp5a4swgXKDEIk0ChknDWaFdwERAQUOjRKCLQeCeYFTAQSPLIs3ghCOc4RJGCmEUF4hLwGCTgEBAQ X-IronPort-AV: E=Sophos;i="5.04,491,1406584800"; d="scan'208";a="78332043" Received: from mail-qg0-f49.google.com ([209.85.192.49]) by mail3-smtp-sop.national.inria.fr with ESMTP/TLS/RC4-SHA; 09 Sep 2014 17:26:27 +0200 Received: by mail-qg0-f49.google.com with SMTP id j5so4152129qga.8 for ; Tue, 09 Sep 2014 08:26:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type; bh=2j+sdBc/wIaZbsVs1BXdzwySGIPK6MlRAszKG6G5ffk=; b=plNQ9B8S2JCNFk7d/WwikLdt80jF8Z3NBrWtF45lkknxNKrGIXLMtGOvyA1FmrG+UZ I83xE1hFm93ZTjkMB6Ue+GDAYF0K9iIwim6fA5UjbbdC38Mn0lbnuQML6kqB6GBdQpIu EvtK1bn4XmW5Ov2+6L7mUZkyirn/o4oEmaDvhcQMT4EO6ASrMhPJ2gnkOTKlfMSwY4tS Hlb01+zHFp4gMyXCiRAvwChRgKA2XLtS1Oq4Z7XYPw1nThOYCs3EfK/dFnBltJ7PKN7i BWPkUH+n0KQgxJQKty2gXqw+PO4S55rvSHyeQqaNQlr9js24vi4kSWFwLdIAYfbWCooJ IZqQ== X-Received: by 10.140.30.74 with SMTP id c68mr49118108qgc.63.1410276385962; Tue, 09 Sep 2014 08:26:25 -0700 (PDT) MIME-Version: 1.0 Received: by 10.224.174.68 with HTTP; Tue, 9 Sep 2014 08:26:01 -0700 (PDT) In-Reply-To: References: From: Yotam Barnoy Date: Tue, 9 Sep 2014 11:26:01 -0400 Message-ID: To: Stephen Dolan Cc: Ocaml Mailing List Content-Type: multipart/alternative; boundary=001a113a672c0563c70502a38f4d Subject: Re: [Caml-list] Multicore runtime --001a113a672c0563c70502a38f4d Content-Type: text/plain; charset=UTF-8 With great care is right :) But seriously, work stealing is a huge undertaking in this model, and may not be feasible at all as far as I can tell. Every private heap object accessed by a thread has to be copied either to the shared heap or to the stealer's heap. This is the downside of not having one shared heap for everything. Of course there are huge upsides as well, but I don't see how work stealing could work efficiently. The only exception would be for a thread that hasn't started running at all, or has allocated very little. On Tue, Sep 9, 2014 at 11:06 AM, Stephen Dolan wrote: > On Tue, Sep 9, 2014 at 3:24 AM, Yotam Barnoy > wrote: > > I have another question about the runtime. I believe it was mentioned in > the > > talk that there would be work-stealing between the domains. But how can > we > > have any work-stealing when the fibers are integrated deeply inside the > > domains' local heaps? > > With great care. > > Stephen > --001a113a672c0563c70502a38f4d Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
With great care is right :) But seriously, work stealing i= s a huge undertaking in this model, and may not be feasible at all as far a= s I can tell. Every private heap object accessed by a thread has to be copi= ed either to the shared heap or to the stealer's heap. This is the down= side of not having one shared heap for everything. Of course there are huge= upsides as well, but I don't see how work stealing could work efficien= tly. The only exception would be for a thread that hasn't started runni= ng at all, or has allocated very little.
On Tue, Sep 9, 2014 at 11:06 AM, Stephen Dolan= <stephen.dolan@cl.cam.ac.uk> wrote:
On Tue, Sep 9, 2014 at 3:24 AM, Yotam = Barnoy <yotambarnoy@gmail.com> wrote:
> I have another question about the runtime. I believe it was mentioned = in the
> talk that there would be work-stealing between the domains. But how ca= n we
> have any work-stealing when the fibers are integrated deeply inside th= e
> domains' local heaps?

With great care.

Stephen

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