An openmp multi-processor version of CNS 1.21 is now available at the
CNS download site
(see http://cns-online.org/cns_request/ to obtain downloading
instructions).
This parallelized version of CNS 1.21 contains openmp directives
(courtesy Kay Diederichs,
Universität Konstanz) that enable parallel computations for some steps
(especially FFTs)
in the crystallographic refinement process on certain linux and mac os
x platforms
using the ifort compiler. By default, the program will utilize the
existing
number of processors on your system for the portions of the code that
are parallelized.
In order to restrict the number of processors to be utilized set the
environmental
variable OMP_NUM_THREADS to the number of processors you want to use.
I have seen performance increases by a factor 2X for medium/large
protein structure
refinements (using task file refine.inp) on 2 x Dual-Core Intel Xeon
processors.
This parallelized version has undergone some testing, but in case you
run into
any problems you should compare the results to the single processor
version. Note,
that the parallel versions uses somewhat different grid sizes for the
electron density grid,
so there will be some small differences between the single and multi-
processor versions.
The only changes compared to the single processor version of CNS 1.21
are in a few
source files, the Makefile compilation files, the test output files,
and the executable cns file.
Axel Brunger
Axel T. Brunger
Investigator, Howard Hughes Medical Institute
Professor of Molecular and Cellular Physiology
Stanford University
Web: http://atbweb.stanford.edu
Email: [EMAIL PROTECTED]
Phone: +1 650-736-1031
Fax: +1 650-745-1463
