add comments

hantmac · Nov 3, 2020 · ad5b262 · ad5b262
1 parent 09ca01f
commit ad5b262
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/03_singleton/singleton_test.go b/03_singleton/singleton_test.go
@@ -22,11 +22,13 @@ func TestParallelSingleton(t *testing.T) {
 	instances := [parCount]*Singleton{}
 	for i := 0; i < parCount; i++ {
 		go func(index int) {
+			//协程阻塞，等待channel被关闭才能继续运行
 			<-start
 			instances[index] = GetInstance()
 			wg.Done()
 		}(i)
 	}
+	//关闭channel，所有协程同时开始运行，实现并行(parallel)
 	close(start)
 	wg.Wait()
 	for i := 1; i < parCount; i++ {