What is context switching of goroutines? Who performs it?

The context switch of goroutines is the process of saving the current goroutine's state and loading the state of another goroutine to continue its execution. Unlike OS threads, goroutines are lightweight and managed by the scheduler within the Go runtime.

The context switch is performed by the goroutine scheduler (scheduler) inside the Go runtime. It decides when to suspend one goroutine and start or resume another, based on available resources and locks.

This allows efficient utilization of system threads and enables concurrency with minimal overhead.

Approximately, it works like this:

• Goroutine A is executing.
• The scheduler decides that goroutine A should be suspended (for example, waiting for I/O).
• The state of goroutine A is saved.
• The state of goroutine B is loaded.
• Goroutine B is executed.

This entire process is transparent to the developer and occurs inside the Go runtime.