In what cases do threads extract goroutines from the shared global task storage?

In Go, threads (M — OS threads) extract goroutines (G) from the shared global task pool (global run queue) in the following cases:

• When a thread is released and ready to execute a new goroutine
• If the local goroutine pool (local run queue) of the thread is empty
• During load balancing between threads, when goroutines are redistributed

In simpler terms, when a thread is not busy executing a goroutine, it tries to get the next goroutine from the global pool to avoid idling. This ensures efficient distribution of goroutines across threads and maximizes CPU resource utilization.

This mechanism is implemented in the Go scheduler, which manages M (threads), P (processor contexts), and G (goroutines).