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Hello Gus and list,<br><br>
I compiled mpich using gcc, no icc. Maybe this could be a good option to
try to obtain better performance.<br><br>
Anyway, maybe I'm wrong as I'm only a (very very basic) user, but I don't
think it is a mpich problem. <br>
Using mpich with n=2, the code speeds up as requested (and I think that 2
different processors are used, looking at htop report). This does not
happen with n=4, where I still observed a (really small) speed-up. But
with n=6 or n=8, no speed-up is observed!<br><br>
Again, I tried to compile with parallel and openmp (and to write a very
simple code with do loop similar to my original simulator, but without
mpi calls, communications, etc ...). I didn't have the expected speed-up
also in this case. I'm still investigating .... but ... I really think
that multi core are a commercial gadget .... unless you are a very
specialist in writing a dedicated code able to take advantage of the
specific architecture of the processor. <br><br>
Hope to be wrong ...<br><br>
Gaetano<br>
<x-sigsep><p></x-sigsep>
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<tt>Gaetano Bellanca - Department of Engineering - University of
Ferrara <br>
Via Saragat, 1 - 44100 - Ferrara -
ITALY
<br>
Voice (VoIP): +39 0532 974809 Fax:
+39 0532 974870<br>
<a href="mailto:gaetano.bellanca@unife.it" eudora="autourl">
mailto:gaetano.bellanca@unife.it</a> <br>
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