Ashley Pittman <ashley <at> pittman.co.uk> writes:
> MPI_Comm_split() is an expensive operation, sure the manual says it's low cost
but it shouldn't be used
> inside any critical loops so be sure you are doing the Comm_Split() at startup
and then re-using it as and
> when needed.
> Any blocking call into OpenMPI will poll consuming CPU cycles until the call
is complete, you can mitigate
> against this by telling OpenMPI to aggressively call yield whilst polling
which would mean that your
> parallel Lapack function could get the CPU resources it required. Have a look
at this FAQ entry for details
> of the option and what you can expect it to do.
Thanks for your detailed responses. Actually, the problem came from a stupied
error of me...
However, I'll have a depth look about the active waiting you describe. I'll try
to see if it affects my performances.