After having compiled potfit with the desired options, the simulation is started as follows:
The name of the potfit program is the same as the compilation target. The parameter file contains all further parameters describing the simulation.
potfit supports MPI parallelization. If MPI is enabled, the number of MPI processes must be stated at the program start. This is usually done with a (system dependent) startup script like the following one:
mpirun -np P potfit_program parameter_file
P is the number of MPI processes.
If MPI is enabled, the reference configurations will be split among the available processors. If you have 10 configurations, it doesn't make sense to use more than 10 CPUs.