Ruby and Python's standard implementations make use of a Global Interpreter Lock. Justin James explains the major advantages and downsides of the GIL mechanism.

A major criticism of the Python programming language is that it can't thread across cores. The reason is because of the CPython's Global Interpreter Lock (GIL). The inability to take advantage of more ...

Moore’s Law and Python’s flawed logic When language architects designed Python, they couldn’t conceive of a world where computers had more than one core. In the 1980s and 1990s, software engineers bet ...

Python 3.13: Better interactive shell and finally multithreading without GIL The new Python release features an interactive command line and allows the global interpreter lock to be deactivated.

Finally, the GIL itself was reworked somewhat in Python 3, with a better thread-switching handler. But all of its underlying assumptions — and limitations — remain.

For multi-threaded workloads, the lack of a GIL allows it to shine, blowing past the default interpreter with an 18x speedup by running 20 threads. Not too shabby.

A new project to change the CPython runtime to boost multithreaded performance has drawn the attention of Python’s core development team.