[Paraview] MPI makes Paraview slower?

[W. Bryan Smith]

[apologies if this was posted twice]

hi,

i am (a major newbie) running paraview in 
parallel mode with mpich2 (1.0.3) on a 2 
dual-core cpu machine using this:

mpiexec -n 4 /usr/local/paraview2.5/bin/paraview/

and many things seem slower than just running 
paraview in single cpu mode.  one of the trivial 
things that is noticably MUCH slower is simply 
loading a file: i have a 500MB file that takes 
about 5 seconds to load in single cpu mode, and 
takes about 30-40 seconds when running in MPI.  
also, no matter if i run in single or MPI, the 
slowest process that i have seen so far 
(PainterPolyDataMapper) only uses a single cpu.  
i am sure there is just something i am doing 
wrong.  any hints on how (if!?) i can change 
this behaviour?  i have ordered the book but it 
has not yet arrived...

thanks,
bryan

W. Bryan Smith
UCSD/NCMIR
9500 Gilman Drive # 0608
La Jolla, CA, 92093-0608

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The illusion that we are separate from one another
is an optical delusion of our consciousness.
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