diff --git a/relay/wshandlers.go b/relay/wshandlers.go
index 6f43aa5..662f69a 100644
--- a/relay/wshandlers.go
+++ b/relay/wshandlers.go
@@ -144,17 +144,15 @@ func (ws *WsServer) handleClientDisconnect(client *client) {
 			channelsToClear = append(channelsToClear, messageChanKey(topic))
 		}
 	}
-
-	if client.role == Dapp {
-		// clear dapp notify channels
-		publishedChannels := []string{}
-		for topic := range client.pubTopics.Get() {
-			ws.publishers.Unset(topic, client)
-			if ws.publishers.Len(topic) == 0 {
-				publishedChannels = append(publishedChannels, dappNotifyChanKey(topic))
+	for topic := range client.pubTopics.Get() {
+		ws.publishers.Unset(topic, client)
+		if ws.publishers.Len(topic) == 0 {
+			channelsToClear = append(channelsToClear, messageChanKey(topic))
+			// for dapp, need to further clear notify channels
+			if client.role == Dapp {
+				channelsToClear = append(channelsToClear, dappNotifyChanKey(topic))
 			}
 		}
-		channelsToClear = append(channelsToClear, publishedChannels...)
 	}
 
 	if len(channelsToClear) > 0 {
diff --git a/relay/wsserver.go b/relay/wsserver.go
index e1ffcae..f499f20 100644
--- a/relay/wsserver.go
+++ b/relay/wsserver.go
@@ -72,7 +72,7 @@ func (ws *WsServer) NewClientConn(w http.ResponseWriter, r *http.Request) {
 		ws:        ws,
 		pubTopics: NewTopicSet(),
 		subTopics: NewTopicSet(),
-		sendbuf:   make(chan SocketMessage, 256),
+		sendbuf:   make(chan SocketMessage, 8),
 		quit:      make(chan struct{}),
 	}