How CPython Manages Memory Using Reference Counting and Garbage Collection

Python handles memory automatically in CPython through two mechanisms: reference counting and a cyclic garbage collector. Every Python object tracks how many references point to it, and when that count drops to zero, CPython immediately deallocates the object. However, reference counting alone cannot resolve cyclic references — cases where objects point to each other and never reach a zero count — so Python includes a separate gc module to handle these. The cyclic collector uses a generational model, sorting objects into three generations based on survival time, with newer objects checked more frequently than older ones. Developers working on performance-sensitive code can disable the cyclic collector manually, provided their code avoids creating reference cycles.