From owner-sc22wg5@open-std.org Thu Jan 22 03:14:45 2009 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 038B8CA3434; Thu, 22 Jan 2009 03:14:45 +0100 (CET) X-Original-To: sc22wg5@open-std.org Delivered-To: sc22wg5@open-std.org Received: from ns.nag-j.co.jp (218-42-159-107.cust.bit-drive.ne.jp [218.42.159.107]) by www2.open-std.org (Postfix) with ESMTP id 1167EC178E0 for ; Thu, 22 Jan 2009 03:14:43 +0100 (CET) Received: from 218-42-159-108.cust.bit-drive.ne.jp ([218.42.159.108] helo=[127.0.0.1]) by ns.nag-j.co.jp with esmtp (Exim 4.50) id 1LPp4p-0002tZ-Bv for sc22wg5@open-std.org; Thu, 22 Jan 2009 11:13:51 +0900 Message-ID: <4977D750.6090506@nag-j.co.jp> Date: Thu, 22 Jan 2009 11:17:52 +0900 From: Malcolm Cohen User-Agent: Thunderbird 3.0a1pre (Windows/2008022014) MIME-Version: 1.0 To: WG5 Subject: [Fwd: Re: (j3.2006) (SC22WG5.3880) [ukfortran] [MPI3 Fortran] MPI non-blocking transfers] Content-Type: multipart/mixed; boundary="------------030405070204030702060407" Sender: owner-sc22wg5@open-std.org Precedence: bulk This is a multi-part message in MIME format. --------------030405070204030702060407 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Aleks seems to have forgotten to send this one to the WG5 list... --------------030405070204030702060407 Content-Type: message/rfc822; name="Re: (j3.2006) (SC22WG5.3880) [ukfortran] [MPI3 Fortran] MPI non-blocking transfers.eml" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename*0="Re: (j3.2006) (SC22WG5.3880) [ukfortran] [MPI3 Fortran] MPI "; filename*1="non-blocking transfers.eml" X-Account-Key: account2 X-Mozilla-Keys: Return-path: Envelope-to: malcolm@nag-j.co.jp Delivery-date: Thu, 22 Jan 2009 09:30:03 +0900 Received: from mail35.messagelabs.com ([62.231.131.195]) by ns.nag-j.co.jp with smtp (Exim 4.50) id 1LPnSM-0002Jj-Mp for malcolm@nag-j.co.jp; Thu, 22 Jan 2009 09:30:03 +0900 X-VirusChecked: Checked X-Env-Sender: j3-bounces@j3-fortran.org X-Msg-Ref: server-6.tower-35.messagelabs.com!1232584250!21370799!1 X-StarScan-Version: 6.0.0; banners=.,-,- X-Originating-IP: [62.231.145.242] Received: (qmail 29806 invoked from network); 22 Jan 2009 00:30:50 -0000 Received: from nagmx1.nag.co.uk (HELO nagmx1.nag.co.uk) (62.231.145.242) by server-6.tower-35.messagelabs.com with SMTP; 22 Jan 2009 00:30:50 -0000 Received: by nagmx1.nag.co.uk (Postfix) id C1CE2120160; Thu, 22 Jan 2009 00:30:55 +0000 (GMT) Delivered-To: malcolm@nag.co.uk Received: from mail189.messagelabs.com (mail189.messagelabs.com [85.158.139.179]) by nagmx1.nag.co.uk (Postfix) with ESMTP id B44BF12015F for ; Thu, 22 Jan 2009 00:30:55 +0000 (GMT) X-VirusChecked: Checked X-Env-Sender: j3-bounces@j3-fortran.org X-Msg-Ref: server-6.tower-189.messagelabs.com!1232584248!21504717!1 X-StarScan-Version: 6.0.0; banners=-,-,nag.co.uk X-Originating-IP: [129.174.65.102] X-SpamReason: No, hits=0.0 required=7.0 tests=SUBJECT_EXCESS_QP Received: (qmail 31877 invoked from network); 22 Jan 2009 00:30:49 -0000 Received: from j3.cos.gmu.edu (HELO j3.cos.gmu.edu) (129.174.65.102) by server-6.tower-189.messagelabs.com with AES256-SHA encrypted SMTP; 22 Jan 2009 00:30:49 -0000 Received: from j3-fortran.org (j3 [127.0.0.1]) by j3.cos.gmu.edu (8.13.1/8.13.1) with ESMTP id n0LNn4qG028695; Wed, 21 Jan 2009 18:49:05 -0500 Received: from nspiron-2.llnl.gov (nspiron-2.llnl.gov [128.115.41.82]) by j3.cos.gmu.edu (8.13.1/8.13.1) with ESMTP id n0LNn12p028692 for ; Wed, 21 Jan 2009 18:49:02 -0500 X-Attachments: None Received: from cyrus2.llnl.gov ([128.15.97.105]) by nspiron-2.llnl.gov with ESMTP; 21 Jan 2009 16:17:53 -0800 From: Aleksandar Donev Organization: LLNL To: fortran standards email list for J3 Date: Wed, 21 Jan 2009 16:17:53 -0800 User-Agent: KMail/1.9.4 References: <20090121234200.4F3BDCA3434@www2.open-std.org> <20090122000407.D5A8ECA3434@www2.open-std.org> In-Reply-To: <20090122000407.D5A8ECA3434@www2.open-std.org> MIME-Version: 1.0 Content-Disposition: inline Message-Id: <200901211617.53468.donev1@llnl.gov> Subject: Re: (j3.2006) =?iso-8859-1?q?=28SC22WG5=2E3880=29_=5Bukfortran=5D_=5B?= =?iso-8859-1?q?MPI3_Fortran=5D=09MPI=09non-blocking_transfers?= X-BeenThere: j3@j3-fortran.org X-Mailman-Version: 2.1.9 Precedence: list Reply-To: fortran standards email list for J3 List-Id: fortran standards email list for J3 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: j3-bounces@j3-fortran.org Errors-To: j3-bounces@j3-fortran.org On Wednesday 21 January 2009 16:04, Van Snyder wrote: > or is there another cause for it? YES!!! Why do we have the ASYNCHRONOUS attribute instead of just having WAIT?!? The compiler must know that a variable can change behind its back, must now not to perform copy in/out and "optimizations", and the standard has several restrictions on ASYNCHRONOUS dummies (see chapter 12). These are all "other causes" and have no connection to WAIT what so ever. And no, this is not a defect with MPI's interface. It is simply another way to do interfaces. Plenty of libraries save pointers and do not ask you to pass the same 100 arguments both for the "start" and the "end" of an operation. It is perfectly sensible design, especially in the C world. Best, Aleks _______________________________________________ J3 mailing list J3@j3-fortran.org http://j3-fortran.org/mailman/listinfo/j3 ________________________________________________________________________ This e-mail has been scanned for all viruses by Star. ________________________________________________________________________ ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________ --------------030405070204030702060407--