diff --git a/app/reverse/portal.go b/app/reverse/portal.go
index 818c5718..3168b59a 100644
--- a/app/reverse/portal.go
+++ b/app/reverse/portal.go
@@ -76,7 +76,7 @@ func (p *Portal) HandleConnection(ctx context.Context, link *transport.Link) err
 			return errors.New("failed to create mux client worker").Base(err).AtWarning()
 		}
 
-		worker, err := NewPortalWorker(muxClient)
+		worker, err := NewPortalWorker(muxClient, p.picker)
 		if err != nil {
 			return errors.New("failed to create portal worker").Base(err)
 		}
@@ -170,7 +170,7 @@ func (p *StaticMuxPicker) PickAvailable() (*mux.ClientWorker, error) {
 		if w.draining {
 			continue
 		}
-		if w.client.Closed() {
+		if w.IsFull() {
 			continue
 		}
 		if w.client.ActiveConnections() < minConn {
@@ -206,14 +206,16 @@ func (p *StaticMuxPicker) AddWorker(worker *PortalWorker) {
 }
 
 type PortalWorker struct {
-	client   *mux.ClientWorker
-	control  *task.Periodic
-	writer   buf.Writer
-	reader   buf.Reader
-	draining bool
+	client       *mux.ClientWorker
+	control      *task.Periodic
+	writer       buf.Writer
+	reader       buf.Reader
+	draining     bool
+	counter      uint32
+	parentPicker *StaticMuxPicker
 }
 
-func NewPortalWorker(client *mux.ClientWorker) (*PortalWorker, error) {
+func NewPortalWorker(client *mux.ClientWorker, picker *StaticMuxPicker) (*PortalWorker, error) {
 	opt := []pipe.Option{pipe.WithSizeLimit(16 * 1024)}
 	uplinkReader, uplinkWriter := pipe.New(opt...)
 	downlinkReader, downlinkWriter := pipe.New(opt...)
@@ -231,9 +233,10 @@ func NewPortalWorker(client *mux.ClientWorker) (*PortalWorker, error) {
 		return nil, errors.New("unable to dispatch control connection")
 	}
 	w := &PortalWorker{
-		client: client,
-		reader: downlinkReader,
-		writer: uplinkWriter,
+		client:       client,
+		reader:       downlinkReader,
+		writer:       uplinkWriter,
+		parentPicker: picker,
 	}
 	w.control = &task.Periodic{
 		Execute:  w.heartbeat,
@@ -244,32 +247,32 @@ func NewPortalWorker(client *mux.ClientWorker) (*PortalWorker, error) {
 }
 
 func (w *PortalWorker) heartbeat() error {
-	if w.client.Closed() {
+	if w.Closed() {
 		return errors.New("client worker stopped")
 	}
 
-	if w.draining || w.writer == nil {
+	if w.writer == nil {
 		return errors.New("already disposed")
 	}
 
 	msg := &Control{}
 	msg.FillInRandom()
 
-	if w.client.TotalConnections() > 256 {
+	if w.draining || w.client.TotalConnections() > 256 {
 		w.draining = true
 		msg.State = Control_DRAIN
 
-		defer func() {
-			common.Close(w.writer)
-			common.Interrupt(w.reader)
-			w.writer = nil
-		}()
+		defer w.tryCloseHeartbeat()
 	}
 
-	b, err := proto.Marshal(msg)
-	common.Must(err)
-	mb := buf.MergeBytes(nil, b)
-	return w.writer.WriteMultiBuffer(mb)
+	w.counter = (w.counter + 1) % 5
+	if w.draining || w.counter == 1 {
+		b, err := proto.Marshal(msg)
+		common.Must(err)
+		mb := buf.MergeBytes(nil, b)
+		return w.writer.WriteMultiBuffer(mb)
+	}
+	return nil
 }
 
 func (w *PortalWorker) IsFull() bool {
@@ -279,3 +282,20 @@ func (w *PortalWorker) IsFull() bool {
 func (w *PortalWorker) Closed() bool {
 	return w.client.Closed()
 }
+
+func (w *PortalWorker) tryCloseHeartbeat() {
+	w.parentPicker.access.Lock()
+	closeable := false
+	for _, wo := range w.parentPicker.workers {
+		if wo != w && !wo.IsFull() && !wo.draining && wo.writer != nil {
+			closeable = true
+			break
+		}
+	}
+	w.parentPicker.access.Unlock()
+	if closeable {
+		common.Close(w.writer)
+		common.Interrupt(w.reader)
+		w.writer = nil
+	}
+}