Introducing the GIL

The GIL is quite popular in the Python concurrent programming community. Designed as a lock that will only allow one thread to access and control the Python interpreter at any given time, the GIL in Python is often known as the infamous GIL that prevents multithreaded programs from reaching their fully optimized speed.

In this section, we will discuss the concept behind the GIL, as well as its purpose: why it was designed and implemented and how it affects multithreaded programming in Python.

Analyzing memory management in Python

Before we jump into the specifics of the GIL and its effects, let's consider the problems that Python core developers encountered during the early days of Python that gave rise to a need for the GIL. Specifically, there is a significant difference between Python programming and programming in other popular languages, in terms of managing objects in the memory space.

For example, in the programming language C++, a variable...