Set TCP_NODELAY on the listen socket only

All unixs inherit NODELAY from the listen socket to the sockets returned
from accept(2), so you only need to set in on the listen socket once to
use it on the client sockets.

Author: evanphx

lib/puma/server.rb

@@ -61,8 +61,12 @@ def initialize(app, events=Events::DEFAULT)
       }
     end
 
-    def add_tcp_listener(host, port)
-      @ios << TCPServer.new(host, port)
+    def add_tcp_listener(host, port, optimize_for_latency=true)
+      s = TCPServer.new(host, port)
+      if optimize_for_latency
+        s.setsockopt(Socket::IPPROTO_TCP, Socket::TCP_NODELAY, 1)
+      end
+      @ios << s
     end
 
     def add_unix_listener(path)
@@ -126,10 +130,6 @@ def handle_check
     end
 
     def process_client(client)
-      if client.kind_of? TCPSocket
-        client.setsockopt(Socket::IPPROTO_TCP, Socket::TCP_NODELAY, 1)
-      end
-
       begin
         while true
           parser = HttpParser.new