Worker pool with channels

A worker pool uses channels to distribute tasks to a fixed number of goroutines for safe, concurrent processing.

A worker pool with channels uses a shared queue channel to distribute tasks to a fixed number of goroutines, which process items concurrently and signal completion. This pattern prevents resource exhaustion by limiting concurrency while maximizing CPU utilization.

package main

import (
	"fmt"
	"sync"
)

func worker(id int, jobs <-chan int, results chan<- int, wg *sync.WaitGroup) {
	defer wg.Done()
	for j := range jobs {
		results <- j * 2
	}
}

func main() {
	jobs := make(chan int, 100)
	results := make(chan int, 100)
	var wg sync.WaitGroup

	// Start 3 workers
	for w := 1; w <= 3; w++ {
		wg.Add(1)
		go worker(w, jobs, results, &wg)
	}

	// Send jobs
	for j := 1; j <= 5; j++ {
		jobs <- j
	}
	close(jobs)

	// Wait for workers to finish
	go func() {
		wg.Wait()
		close(results)
	}()

	// Collect results
	for r := range results {
		fmt.Println(r)
	}
}