AMBER Archive (2002)

Subject: Re: "number of processors must be a power of two"

From: Michael Crowley (crowley_at_scripps.edu)
Date: Tue Aug 06 2002 - 12:31:50 CDT


Dear Jim,
The power-of-two is required now for sander (amber7) since
we implemented the binary tree for
force and coordinate communications at each step.
It necessary for all parallel platforms now. It is a
change from amber6 in which there was no
such restriction. The improvement in performance
is significant enough that it was hardened into
the program rather than being an option.
Future versions may have this restriction eliminated.
Mike

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Physical mail: Dr. Michael F. Crowley
                 Department of Molecular Biology, TPC6
                 The Scripps Research Institute
                 10550 North Torrey Pines Road
                 La Jolla, California 92037

Electronic mail: crowley_at_scripps.edu
Telephone: 858/784-9290
Fax: 858/784-8688
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