В чем преимущества goroutines перед OS threads?

Goroutines have several key advantages over traditional OS threads:

• Lightweight: a goroutine takes a few kilobytes of memory at startup, whereas an OS thread uses megabytes. This allows thousands or even millions of goroutines to run concurrently.

• Fast creation and switching: context switching between goroutines is faster because it is managed by the Go runtime, not the OS kernel.

• Go scheduler: the built-in scheduler efficiently distributes goroutines across available OS threads, optimizing CPU usage.

• Simple synchronization: Go provides channels and other primitives for safe data exchange between goroutines, simplifying concurrent programming.

Example of creating a goroutine:

func sayHello() {
    fmt.Println("Hello from goroutine")
}

func main() {
    go sayHello() // runs the function in a separate goroutine
    time.Sleep(time.Second) // wait to allow the goroutine to complete
}

Thus, goroutines make writing concurrent code simpler and more efficient than directly using OS threads.