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Date: 03 Dec 2008 09:57:59 +0000
From: "N.M. Maclaren" <nmm1@cam.ac.uk>
To: sc22wg5 <sc22wg5@open-std.org>
Subject: Re: [ukfortran] (SC22WG5.3705)  Atomic stuff
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Sorry.  I mangled this.

>Secondly, and more seriously, atomic accesses will need some sort of an
>inter-image handshake on most systems - even most SMP systems often need
>extra instructions to synchronise the memory subsystem.

What I should have said is that most SMP systems impose constraints on the
instructions used, and some need extra instructions.


Regards,
Nick Maclaren,
University of Cambridge Computing Service,
New Museums Site, Pembroke Street, Cambridge CB2 3QH, England.
Email:  nmm1@cam.ac.uk
Tel.:  +44 1223 334761    Fax:  +44 1223 334679