W dniu 22.03.2020 o 17:31, Dr. Guido Dhondt pisze:
Using "parallel" does not bring anything, unfortunately, I still get "nan" after a couple of hundred iterations.
I run the software in a serial way, however, the software uses pthread to create threads. If $OMP_NUM_THREADS=n it uses n threads. To run CalculiX in a serial way I set OMP_NUM_THREADS=1. So, each time a system of equations has to be solved 1 thread is created. This happens thousands of times, since most examples require 5000 or more iterations, in each iteration the equation system is solved up to 5 times (pressure, velocity...).I do not know whether the thread creation could be a problem?
Guido
That's some important info! OMP_NUM_THREADS is used by OpenMP library, that creates threads for parallel computation inside application. In this case I think it makes more sense to run the program sequentially, allowing it to use all threads. You gain nothing by running them in paralell, where each one is using only one thread. But, regardless of how they are run, it shouldn't affect the results of computations.