Very basic example of a non-queueing worker pool + bouncer in go

bouncer.go

package main

import (
	"fmt"
	"time"
)

func main() {
	concurrency := 10
	bouncer := make(chan bool, concurrency)
	for i := 0; i < concurrency; i++ {
		bouncer <- true
	}

	work := 0
	bounces := 0

	Loop:
	for {
		select {
		case worker := <- bouncer:
			go func() {
				time.Sleep(5 * time.Millisecond)
				work += 1
				bouncer <- worker
			}()
		default:
			bounces += 1
			if work > 50 {
				break Loop
			}
		}
	}

	fmt.Printf("Work: %d\n", work)
	fmt.Printf("Bounces: %d\n", bounces)
}