Allow uniform modification of nb_workers #139
Description
I'm opening a new issue as I've stumble upon the same issue and went back the same pain again #14.
For certain cases (e.g. development on windows or mac), we should be able to run the process with a single thread without too much hassle, and we might want to revisit how the nb_workers are set.
How about making the nb_workers a parameter (default=6, 0=disabled, -1=number of cpu/gpu, n=fixed number) and coordinate it with the multiprocessing variable?