I hate how these threads always devolve in insane discussions about why not using threads is better, while most real world people who have tried to do real world speeding up of Python code realize how amazing it would be to have proper threads with shared memory instead of the processes that have so many limitations, like forcing to pickle objects back and forth, & fork so often just not working in the cloud setting, & spawn being so slow in a lot of applications. The usage of processes is just much heavier and less straightforward.