test.go

package main

import (
	"fmt"
	"log"
	"net/http"
	"os"
	"sync"
	"time"
)

func main() {
	start := &sync.WaitGroup{}
	end := &sync.WaitGroup{}

	log.Println("pid: %d", os.Getpid())

	http.HandleFunc("/test", func(w http.ResponseWriter, r *http.Request) {
		time.Sleep(time.Minute)
		_, err := fmt.Fprintf(w, "Hello!")
		if err != nil {
			log.Println("print error: ", err)
		}
	})
	go func() {
		log.Fatal(http.ListenAndServe(":8080", nil))
	}()

	time.Sleep(5 * time.Second)
	for i := 0; i < 9999; i++ {
		start.Add(1)
		end.Add(1)
		go func() {
			start.Done()
			_, err := http.Get("http://localhost:8080/test")
			if err != nil {
				log.Println("get error: ", err)
			}
			end.Done()
		}()
	}

	start.Wait()
	log.Println("Ready: ", time.Now())
	end.Wait()
	log.Println("Finished: ", time.Now())
}