I can see how using multiprocessing trumps threads for smaller programs. However it can become memory inefficient to have larger programs running in multiple processes, especially on servers with less resources.
If I run N versions of program that occupies 8mb of memory the memory footprint of the code is much less than N*8mb due to shared libraries/memory pages.
It's a factor, sure. But, one you should weigh with other factors to determine what is best.
