Beyond the GIL: Python's Journey to Free Threading

Yonatan Bitton Yonatan Bitton
Language: Hebrew
The presentation was given on 2025.09.09 at PyCon Israel 2025 - Conference.

Explore Python’s groundbreaking shift beyond the Global Interpreter Lock (GIL). Understand the design tradeoffs, challenges, and performance impacts of running Python without the GIL.

The Global Interpreter Lock (GIL) has been a key part of Python's design, simplifying memory management but limiting parallelism in multi-threaded programs. Recent changes now allow Python to run without the GIL, unlocking true parallelism.

In this talk, we'll explore the implications of this shift: the internal changes to Python, the tradeoffs made for thread safety and performance, and the challenges overcome in the process. We’ll compare execution with and without the GIL through examples and benchmarks, and discuss the potential impact on Python developers and the ecosystem.

Whether you’re interested in Python’s internals, concurrency, or its evolving design, this session will provide a concise and practical overview of one of Python’s most significant updates.