The overhead of copying and moving data around in Python is frustrating. When you are CPU bound on a task, you can't use threads (which do have shared memory) b

The overhead of copying and moving data around in Python is frustrating. When you are CPU bound on a task, you can't use threads (which do have shared memory) because of the GIL, so you end up using whole processes and then waste a bunch of cycles communicating stuff back and forth. And yes, you can create shared memory buffers between Python processes but that is nowhere near as smooth as say two Java threads working off a shared data structure that's got synchronized sprinkled on it.