src/Pure/System/system_channel.scala

--- a/src/Pure/System/system_channel.scala	Thu Oct 04 15:25:58 2018 +0100
+++ b/src/Pure/System/system_channel.scala	Thu Oct 04 16:40:03 2018 +0200
@@ -26,7 +26,6 @@
   def rendezvous(): (OutputStream, InputStream) =
   {
     val socket = server.accept
-    socket.setTcpNoDelay(true)
     (socket.getOutputStream, socket.getInputStream)
   }