Can you explain how the task scheduler works in the system?

The task scheduler in the system is responsible for managing the execution of multiple tasks or processes, allocating CPU resources, and ensuring efficient use of time. In operating systems, the scheduler decides which task should run and when, based on priorities, task states, and scheduling algorithms (e.g., Round Robin, priority scheduling, multi-level queues).

In the context of Go (Golang), the goroutine scheduler operates as a lightweight task scheduler within the runtime. It distributes goroutines (lightweight threads) across OS system threads, switching them for efficient CPU utilization. The Go scheduler uses an M:N model, where M is the number of system threads and N is the number of goroutines. This allows thousands of goroutines to run with minimal overhead.

Example of simple goroutine launch in Go:

package main

import (
    "fmt"
    "time"
)

func task(id int) {
    fmt.Printf("Task %d started\n", id)
    time.Sleep(time.Second)
    fmt.Printf("Task %d finished\n", id)
}

func main() {
    for i := 1; i <= 3; i++ {
        go task(i) // launching a goroutine
    }
    time.Sleep(2 * time.Second) // wait for goroutines to finish
}

Here, the Go scheduler manages the execution of three goroutines, switching them on available OS threads.