[gmx-users] G5 performance tweaks

[David]

On Wed, 2004-05-26 at 00:42, Pascal Mercier wrote:
> On a 2GHz G5 after trying different compilation flags I managed to
> gota score of 11220 for the Villin test (with 1 CPU), using the
> buildscripts below for FFTW and Gromacs (and 11518 using xlf_r,
> xlc_r,xlc++_r).  This only represents a 9% increase in speed compared
> to the1.6 GHz G5 as reported on the benchmark results web page,
> whereas a25% increase in speed would be expected with a theoretical
> speedincrease proportional to the clock speed.  Which flags are
> recommendedfor a xlf/xlc build of Gromacs on OSX?
> 
> Has anyone tried to port Gromacs to Xgrid using the MacMPI
> relatedfortran and C files available
> athttp://exodus.physics.ucla.edu/appleseed/dev/developer.html?  
> 
> Thanks in advance for any tips.
Try without fortran, unless you are sure that the Altivec routines are 
used. Then you could look for other optimization flags.

I will add my Opteron results as well.
-- 
David.
________________________________________________________________________
David van der Spoel, PhD, Assoc. Prof., Molecular Biophysics group,
Dept. of Cell and Molecular Biology, Uppsala University.
Husargatan 3, Box 596,  	75124 Uppsala, Sweden
phone:	46 18 471 4205		fax: 46 18 511 755
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://xray.bmc.uu.se/~spoel
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