How does the garbage collector work?

In Go, the garbage collector (GC) is implemented as a three-phase, concurrent process using the "mark-and-sweep" tracing algorithm.

Main stages of GC operation:

1. Mark: The collector starts with root objects (global variables, goroutine stacks) and recursively marks all accessible objects as live.

2. Sweep: After marking, all objects not marked as live are considered garbage and are freed.

3. Concurrency: The collector runs in parallel with the program execution, minimizing pauses. Go GC aims to keep pauses in the millisecond range.

Go GC is optimized for low latency and scales with the number of processors. It automatically manages memory, freeing the programmer from manual memory management.

Example: if you create objects and stop referencing them, GC will eventually free the memory used by these objects without your intervention.