Advanced Python Programming

Implementing multiprocessing, rather than multithreading 

This is perhaps the most popular and easiest method to circumvent the GIL and achieve optimal speed in a concurrent program. As the GIL only prevents multiple threads from executing CPU-bound tasks simultaneously, processes executing over multiple cores of a system, each having its own memory space, are completely immune to the GIL.

Specifically, considering the preceding countdown example, let's compare the performance of that CPU-bound program when it is sequential, multithreading, and multiprocessing. Navigate to the Chapter22/example3.py file; the first part of the program is identical to what we saw earlier, but at the end we add in an implementation of a multiprocessing solution ...