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leaf May 7, 2006 23:00

How to improve CPU utility when program with mpi?
 
My CPU utility is about 5% under windows XP sp2 environment on 4 computers. Memory of each computer is 1GB. To enchance CPU utilization, what should be noticed when programming with mpi?

Renato. May 8, 2006 10:24

Re: How to improve CPU utility when program with m
 
Probably your program has been stalling in some MPI communication waiting some feedback from other processes. It can be also due unbalanced processes. For a good starting point, it would be useful to measure the wall time spent in each routine to see where your bottleneck is. You can easily do it issuing MPI_WTIME callings (or cpu_time if you're working in Fortran) before and after your routines and accumulating and printing the time spent.

Cheers

Renato.



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