[Wien] Speed versus size (e.g. RKMAX)

[L. D. Marks]

We've run across something odd which someone might know about, and the 
answer may well be generally useful for Wien2k calculations. With our 
older cluster (3.4 P4 with 512L2) once the total size of the calculation 
(i.e. top) gets above about 1G the speed (mflops) drops. We have a newer 
cluster (3.4 P4 with 1024L2) which is about 5% slower for the benchmark, 
but shows a similar drop in speed now for a much smaller size (about 
500Mb). I suspect that this has to be some sort of "tuning" parameter in 
the kernel, but don't know which one and which way to start adjusting. Any 
suggestions?

Note: if you have an old email address for me, please note that "nwu" has
been changed to "northwestern".
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Laurence Marks
Department of Materials Science and Engineering
MSE Rm 2036 Cook Hall
2220 N Campus Drive
Northwestern University
Evanston, IL 60201, USA
Tel: (847) 491-3996 Fax: (847) 491-7820
email: L-marks at northwestern dot edu
http://www.numis.northwestern.edu
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