Limit conccurent container creates in TestEventsLimit to 8

Signed-off-by: Darren Stahl <darst@microsoft.com>

integration-cli/docker_cli_events_test.go

@@ -10,7 +10,6 @@ import (
 	"os"
 	"os/exec"
 	"strings"
-	"sync"
 	"time"
 
 	eventtypes "github.com/docker/docker/api/types/events"
@@ -79,14 +78,17 @@ func (s *DockerSuite) TestEventsUntag(c *check.C) {
 }
 
 func (s *DockerSuite) TestEventsLimit(c *check.C) {
-	var waitGroup sync.WaitGroup
-	errChan := make(chan error, 17)
+	// Limit to 8 goroutines creating containers in order to prevent timeouts
+	// creating so many containers simultaneously on Windows
+	sem := make(chan bool, 8)
+	numContainers := 17
+	errChan := make(chan error, numContainers)
 
 	args := []string{"run", "--rm", "busybox", "true"}
-	for i := 0; i < 17; i++ {
-		waitGroup.Add(1)
+	for i := 0; i < numContainers; i++ {
+		sem <- true
 		go func() {
-			defer waitGroup.Done()
+			defer func() { <-sem }()
 			out, err := exec.Command(dockerBinary, args...).CombinedOutput()
 			if err != nil {
 				err = fmt.Errorf("%v: %s", err, string(out))
@@ -95,7 +97,10 @@ func (s *DockerSuite) TestEventsLimit(c *check.C) {
 		}()
 	}
 
-	waitGroup.Wait()
+	// Wait for all goroutines to finish
+	for i := 0; i < cap(sem); i++ {
+		sem <- true
+	}
 	close(errChan)
 
 	for err := range errChan {