I'm trying to wrap my head around the internals of Python, specifically the Global Interpreter Lock (GIL). Is it true that each process has its own GIL, or is there just one for the entire machine? I assume the GIL is in place for garbage collection, and since each process has its own memory space, it would make sense for there to be one GIL per process. Additionally, the `multiprocessing` module claims to allow true parallelism, which further leads me to believe there is a separate GIL for each process. I'm finding it tough to find confirmation on this. Can anyone clarify?
2 Answers
Yes, each Python process operates with its own GIL! So when you use the `multiprocessing` module, you can achieve true parallelism because each process runs independently without sharing the same GIL. Just a little heads up though, there are also special versions like Python 3.13t and 3.14t that introduce some options for more parallelism within the GIL itself if you need it!
This has been around for a while, but yeah, it might feel like old news with the newer versions like 3.14. Just remember that the GIL is still the default behavior, and opting out of it is something you have to choose to do in your code.
Exactly! Even with new releases, many of us still work with older versions. It's crucial to understand how it works across different Python iterations to avoid surprises.