Add concurrent service sync flag to CCM

cmd/cloud-controller-manager/app/options/options.go

@@ -97,7 +97,7 @@ func (s *CloudControllerManagerServer) AddFlags(fs *pflag.FlagSet) {
 	fs.Float32Var(&s.KubeAPIQPS, "kube-api-qps", s.KubeAPIQPS, "QPS to use while talking with kubernetes apiserver.")
 	fs.Int32Var(&s.KubeAPIBurst, "kube-api-burst", s.KubeAPIBurst, "Burst to use while talking with kubernetes apiserver.")
 	fs.DurationVar(&s.ControllerStartInterval.Duration, "controller-start-interval", s.ControllerStartInterval.Duration, "Interval between starting controller managers.")
-
+	fs.Int32Var(&s.ConcurrentServiceSyncs, "concurrent-service-syncs", s.ConcurrentServiceSyncs, "The number of services that are allowed to sync concurrently. Larger number = more responsive service management, but more CPU (and network) load")
 	leaderelectionconfig.BindFlags(&s.LeaderElection, fs)
 
 	utilfeature.DefaultFeatureGate.AddFlag(fs)