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Subject: Re: Robert Dewar's great article about the Strengths of Ada over
  other langauges in multiprocessing!
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From: Ole-Hjalmar Kristensen
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Date: 10 Mar 2008 10:56:14 +0100
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>>>>> "DAK" == Dmitry A Kazakov <mailbox@dmitry-kazakov.de> writes:

<snip>

    DAK> As for multi-cores, I guess that protected object would not be a good
    DAK> concurrency primitive for such architectures. In a long term perspective,
    DAK> we could experience the pendulum swinging back to tasks.

    DAK> -- 
    DAK> Regards,
    DAK> Dmitry A. Kazakov
    DAK> http://www.dmitry-kazakov.de

I agree. Sharing data between cores or CPUs will give you a
performance hit with todays architectures since it typically makes the
caches much less effective, in addition to the synchroniz<tion cost
itself. In many cases it is better if you can partition your data in
the beginning of the computation and assign a partition of the problem
to each core so they can run without syncronization and assemble the
result at the end. This way, at least you have to think of the cost
associated with exchanging data between tasks or cores.

-- 
   C++: The power, elegance and simplicity of a hand grenade.