fix grpc conn Multiplexing

operate/client.go

@@ -9,8 +9,20 @@ import (
 	"google.golang.org/grpc/credentials/insecure"
 )
 
+var (
+	rpcClientMap map[string]*grpc.ClientConn
+)
+
+func init() {
+	rpcClientMap = make(map[string]*grpc.ClientConn, 0)
+}
+
 func ConnNmGrpc(endpoint string) nodemanagerV2.NodeManagerServiceClient {
-	conn := connGrpc(endpoint)
+	conn := rpcClientMap[endpoint]
+	if conn == nil {
+		conn = connGrpc(endpoint)
+		rpcClientMap[endpoint] = conn
+	}
 	if conn != nil {
 		return nodemanagerV2.NewNodeManagerServiceClient(conn)
 	}