刚才的问题原因是测试程序中conn.close(）未释放导致

client/main.go

@@ -28,13 +28,14 @@ func main() {
 			continue
 		}
 
-		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
 		// conn, err := grpc.Dial("127.0.0.1:9001", grpc.WithBlock(), grpc.WithInsecure())
 		conn, err := grpc.DialContext(ctx, fmt.Sprintf("%s:%d", node.Address, node.Port), grpc.WithBlock(), grpc.WithInsecure(), grpc.WithBalancerName("round_robin"))
 		if err != nil {
+			fmt.Printf("%v\n", err)
 			cancel()
 		}
-		defer conn.Close()
+
 		c := pb.NewHelloClient(conn)
 		resp, err := c.Say(ctx, &pb.SayRequest{Name: "jiale", Day: "2008-08-08"})
 		if err != nil {
@@ -45,6 +46,6 @@ func main() {
 		log.WithFields(log.Fields{
 			"func": "main",
 		}).Infof("%s", resp.Reply)
-
+		conn.Close()
 	}
 }