Does SPHERAL automatically turn on the parallel run?

[Edithnuaa]

I want to speed up my program through increasing the number of MPI tasks.

I run the example.py by this command:

mpiexec -n 4 ./spheral example.py

However, the procedure becomes significantly slow. And when I run the example through mpiexec -n 1 ./spheral example.py, the speed of the procedure seems to be equal to the command without mpiexec.

Is it possible to utilize the ability of MPI? Or does the SPHERAL already handle this functionality inside?