Mis on goroutines?

Lightweight execution threads managed by the Go runtime. They are created with the go keyword before calling a function.

Main features:

• Lower memory consumption: A goroutine starts with a small stack size (usually 2 KB), which can grow or shrink dynamically.
• Faster creation: Creating a goroutine is much faster than creating a system thread.
• Multiplexing onto system threads: Many goroutines can be multiplexed onto fewer system threads by the Go runtime scheduler.
• Cooperative scheduling: Goroutines are not preemptively interrupted; they voluntarily yield control to the scheduler (e.g., during blocking calls or explicit runtime.Gosched() calls).

Example of creation:

package main

import (
	"fmt"
	"time"
)

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

func main() {
	go sayHello() // Launch sayHello as a goroutine
	fmt.Println("Hello from main function!")
	time.Sleep(1 * time.Second) // To prevent main from finishing before goroutine
}

Comparison with threads:

Attribute	Go Goroutines	OS Threads
Management	Go runtime	Operating system
Memory usage	Low, dynamic stack	High, fixed stack
Creation	Fast	Slow
Scheduling	Cooperative	Preemptive
Synchronization	Channels, sync package	Mutexes, OS semaphores