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 mail1-relais-roc.national.inria.fr (mail1-relais-roc.national.inria.fr [192.134.164.82]) by yquem.inria.fr (Postfix) with ESMTP id E58DBBBCD for ; Fri, 9 May 2008 21:55:03 +0200 (CEST) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AmgDAPNIJEjUnw7Ub2dsb2JhbACCMY9WAQwFAgQHEwOZMA X-IronPort-AV: E=Sophos;i="4.27,462,1204498800"; d="scan'208";a="12048915" Received: from ptb-relay01.plus.net ([212.159.14.212]) by mail1-smtp-roc.national.inria.fr with ESMTP; 09 May 2008 21:55:03 +0200 Received: from [80.229.56.224] (helo=beast.local) by ptb-relay01.plus.net with esmtp (Exim) id 1JuYgH-0005jM-7c; Fri, 09 May 2008 20:55:01 +0100 From: Jon Harrop Organization: Flying Frog Consultancy Ltd. To: "Ulf Wiger (TN/EAB)" Subject: Re: not all functional languages lack parallelism Date: Fri, 9 May 2008 19:10:08 +0100 User-Agent: KMail/1.9.9 References: <200805090139.54870.jon@ffconsultancy.com> <4824448C.9030102@ericsson.com> In-Reply-To: <4824448C.9030102@ericsson.com> Cc: caml-list@yquem.inria.fr MIME-Version: 1.0 Content-Disposition: inline Message-Id: <200805091910.08348.jon@ffconsultancy.com> Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Plusnet-Relay: 6b3425edbe22c2e862bc70d7911f2637 X-Spam: no; 0.00; parallelism:01 parallelism:01 scalable:01 jocaml:01 erlang:01 statically:01 erlang:01 20,000:98 ubuntu:98 smoke:98 frog:98 wrote:01 computation:01 functional:02 functional:02 On Friday 09 May 2008 13:33:16 Ulf Wiger wrote: > Jon Harrop skrev: > > 1. Lack of Parallelism: Yes, this is already a complete show > > > > stopper. Exploiting multicores requires a scalable concurrent > > GC and message passing (like JoCaml) is not a substitute. > > Unfortunately, this is now true of all functional languages > > available for Linux, which is why we have now migrated > > > > entirely to Windows and F#. > > Dear Jon, > > I will keep reminding you that Erlang is a functional language > (just not a statically typed one). It has very lightweight > processes, concurrent schedulers on multicore, and per-process > GC. It scales very well on multicore. I will keep reminding you at Erlang is not competitively performance for CPU-bound computation like number crunching. The fact that it scales well on distributed clusters for massively concurrent applications is irrelevant: that has nothing to do with multicore computing. > "Under some pretty extreme loads - around 20,000 open > mainframe connections - I was blowing up Erlyweb/Yaws. > As a sanity check, this was when Erlyweb/Yaws was > consuming ~90% of all 4 CPUs on a dedicated newish > Dell server running Ubuntu 7.10 server; there was > probably smoke coming out of the box at the time ;-> If this were relevant to multicore computing, an "extreme load" would certainly be 100% CPU usage and not 90%. -- Dr Jon D Harrop, Flying Frog Consultancy Ltd. http://www.ffconsultancy.com/products/?e