From owner-sc22wg5@open-std.org Thu Nov 6 20:48:16 2008 Return-Path: X-Original-To: sc22wg5-dom7 Delivered-To: sc22wg5-dom7@www2.open-std.org Received: by www2.open-std.org (Postfix, from userid 521) id 7ED0BCA5FE8; Thu, 6 Nov 2008 20:48:16 +0100 (CET) X-Original-To: sc22wg5@open-std.org Delivered-To: sc22wg5@open-std.org X-Greylist: delayed 767 seconds by postgrey-1.18 at www2.open-std.org; Thu, 06 Nov 2008 20:48:15 CET Received: from over.ny.us.ibm.com (over.ny.us.ibm.com [32.97.182.150]) by www2.open-std.org (Postfix) with ESMTP id BE318CA343A for ; Thu, 6 Nov 2008 20:48:14 +0100 (CET) Received: from e6.ny.us.ibm.com ([192.168.1.106]) by pokfb.esmtp.ibm.com (8.12.11.20060308/8.12.11) with ESMTP id mA6JZTDc030886 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 6 Nov 2008 14:35:29 -0500 Received: from d01relay04.pok.ibm.com (d01relay04.pok.ibm.com [9.56.227.236]) by e6.ny.us.ibm.com (8.13.8/8.13.8) with ESMTP id mA6JcEkY014127 for ; Thu, 6 Nov 2008 14:38:14 -0500 Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by d01relay04.pok.ibm.com (8.13.8/8.13.8/NCO v9.1) with ESMTP id mA6JZGZv085200 for ; Thu, 6 Nov 2008 14:35:16 -0500 Received: from d01av01.pok.ibm.com (loopback [127.0.0.1]) by d01av01.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id mA6JZGGD005446 for ; Thu, 6 Nov 2008 14:35:16 -0500 Received: from d25ml04.torolab.ibm.com (d25ml04.torolab.ibm.com [9.26.6.105]) by d01av01.pok.ibm.com (8.12.11.20060308/8.12.11) with ESMTP id mA6JZGA1005438; Thu, 6 Nov 2008 14:35:16 -0500 In-Reply-To: <20081106183106.C45D4CA343A@www2.open-std.org> References: <20081106000140.7BDFCCA3434@www2.open-std.org> <20081106084230.BD64BCA343A@www2.open-std.org> <20081106183106.C45D4CA343A@www2.open-std.org> To: longb@cray.com, fortran standards email list for J3 Cc: j3-bounces@j3-fortran.org, sc22wg5 MIME-Version: 1.0 Subject: Re: (j3.2006) (SC22WG5.3633) [ukfortran] [Fwd: Preparing for the Tokyo meeting] X-Mailer: Lotus Notes Release 8.0.1 HF105 April 10, 2008 Message-ID: From: Jim Xia Date: Thu, 6 Nov 2008 14:35:14 -0500 X-MIMETrack: Serialize by Router on D25ML04/25/M/IBM(Release 7.0.3FP1|February 24, 2008) at 11/06/2008 14:35:15, Serialize complete at 11/06/2008 14:35:15 Content-Type: multipart/alternative; boundary="=_alternative 006B97E3852574F9_=" Sender: owner-sc22wg5@open-std.org Precedence: bulk This is a multipart message in MIME format. --=_alternative 006B97E3852574F9_= Content-Type: text/plain; charset="US-ASCII" j3-bounces@j3-fortran.org wrote on 11/06/2008 01:28:36 PM: > [image removed] > > (j3.2006) (SC22WG5.3633) [ukfortran] [Fwd: Preparing for the Tokyo meeting] > > Bill Long > > Vectorization (either SSE or X2) is not an alternative to coarrays. > They coexist and complement each other. SSE is still vectorization. > And I would expect the length of the registers to get longer in the > future as chip vendors try to boost performance at fixed clock rates. > > > b) Because of that, SSE optimisations are handled by all compilers in > > similar ways to instruction scheduling, and not like true vectorisation, as > > was used on the IBM 3090, Hitachi S-3600, many Fujitsus, almost all Crays > > and so on. > > > > > > I can't speak for IBM, Hitachi, or Fujitsu, but at least I know now you > are not aware of what happens in Cray's compiler. You certainly can't speak for IBM :-) And we can discuss these issues during the Tokyo meeting. BTW I really lost track on the topics discussed in this *LONG* thread of "Preparing for the Tokyo meeting". But two points I was surprised to see: 1.) there are people assume compiler will only support coarray (i.e. abandon serial Fortran) if coarrays are kept in F08. It's rather a disturbing argument. 2.) I certainly don't see how vectorization replaces parallel programming. Many Fortran programmers may have never used a vector machine, but I'll be surprised if they never used a multi-processor machine. Cheers, Jim Xia RL Fortran Compiler Test IBM Toronto Lab at 8200 Warden Ave, Markham, On, L6G 1C7 Phone (905) 413-3444 Tie-line 313-3444 email: jimxia@ca.ibm.com D2/YF7/8200 /MKM --=_alternative 006B97E3852574F9_= Content-Type: text/html; charset="US-ASCII"
j3-bounces@j3-fortran.org wrote on 11/06/2008 01:28:36 PM:

> [image removed]
>
> (j3.2006) (SC22WG5.3633) [ukfortran] [Fwd: Preparing for the Tokyo meeting]
>
> Bill Long
>
> Vectorization (either SSE or X2)  is not an alternative to coarrays.  
> They coexist and complement each other.  SSE is still vectorization.  
> And I would expect the length of the registers to get longer in the
> future as chip vendors try to boost performance at fixed clock rates.
>
> >     b) Because of that, SSE optimisations are handled by all compilers in
> > similar ways to instruction scheduling, and not like true vectorisation, as
> > was used on the IBM 3090, Hitachi S-3600, many Fujitsus, almost all Crays
> > and so on.
> >
> >  
>
> I can't speak for IBM, Hitachi, or Fujitsu, but at least I know now you
> are not aware of what happens in Cray's compiler.

You certainly can't speak for IBM :-)  And we can discuss these issues during the Tokyo meeting.  BTW I really lost track on the topics discussed in this *LONG* thread of "Preparing for the Tokyo meeting".  But two points I was surprised to see: 1.) there are people assume compiler will only support coarray (i.e. abandon serial Fortran) if coarrays are kept in F08.  It's rather a disturbing argument.  2.) I certainly don't see how vectorization replaces parallel programming.  Many Fortran programmers may have never used a vector machine, but I'll be surprised if they never used a multi-processor machine.

Cheers,

Jim Xia

RL Fortran Compiler Test
IBM Toronto Lab at 8200 Warden Ave, Markham, On, L6G 1C7
Phone (905) 413-3444  Tie-line 313-3444
email: jimxia@ca.ibm.com
D2/YF7/8200 /MKM
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