diff --git a/proxy/vmess/vmessin.go b/proxy/vmess/vmessin.go
index 697e07f8..5564c66e 100644
--- a/proxy/vmess/vmessin.go
+++ b/proxy/vmess/vmessin.go
@@ -96,7 +96,7 @@ func (handler *VMessInboundHandler) HandleConnection(connection net.Conn) error
 	}
 
 	// Optimize for small response packet
-	buffer := make([]byte, 0, 2*1024)
+	buffer := make([]byte, 0, 4*1024)
 	buffer = append(buffer, request.ResponseHeader...)
 
 	if data, open := <-output; open {