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From: George Bosilca (bosilca_at_[hidden])
Date: 2006-10-27 15:39:52


No documentation yet. If you want to understand how it works and what
exactly "highly optimized" means please look for the collectives
papers on this page (http://www.netlib.org/utk/people/JackDongarra/
papers.htm). In few words, we have multiples algorithms and we tune
them based on the network characteristics.

We have a home made tools that help us with that. It's far from
complete, but it's enough for what we're doing right now. If you
want, I can give you the source code and the documentation and you
can play around with it.

Thanks,
   george.

On Oct 27, 2006, at 2:56 PM, Tony Ladd wrote:

> George
>
> Thanks for the info. When you say "highly optimized" do you
> algorithmically,
> tuning, or both? In particular I wonder if OMPI optimized
> collectives use
> the divide and conquer strategy to maximize network bandwidth.
>
> Sorry to be dense but I could not find documanetation on how to
> access the
> optimized collectives. I would be willing to fiddle with the
> parameters a
> bit by hand if I had some guidance as to how to set things and what
> I might
> vary.
>
> The optimization I was talking about (divide and conquer) would
> work better
> than the basic strategy regardless of network; only message size
> might have
> some effect.
>
> Thanks
>
> Tony
>
>
> -------------------------------
> Tony Ladd
> Chemical Engineering
> University of Florida
> PO Box 116005
> Gainesville, FL 32611-6005
>
> Tel: 352-392-6509
> FAX: 352-392-9513
> Email: tladd_at_[hidden]
> Web: http://ladd.che.ufl.edu
>
>
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