Implementations of TCP and IPC transports separated

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/src/tcp_listener.cpp b/src/tcp_listener.cpp
index d334768..360be8c 100644
--- a/src/tcp_listener.cpp
+++ b/src/tcp_listener.cpp
@@ -87,6 +87,26 @@ void zmq::tcp_listener_t::in_event ()
     if (fd == retired_fd)
         return;
 
+    //  Disable Nagle's algorithm. We are doing data batching on 0MQ level,
+    //  so using Nagle wouldn't improve throughput in anyway, but it would
+    //  hurt latency.
+    int nodelay = 1;
+    int rc = setsockopt (fd, IPPROTO_TCP, TCP_NODELAY, (char*) &nodelay,
+        sizeof (int));
+#ifdef ZMQ_HAVE_WINDOWS
+    wsa_assert (rc != SOCKET_ERROR);
+#else
+    errno_assert (rc == 0);
+#endif
+
+#ifdef ZMQ_HAVE_OPENVMS
+    //  Disable delayed acknowledgements as they hurt latency is serious manner.
+    int nodelack = 1;
+    rc = setsockopt (fd, IPPROTO_TCP, TCP_NODELACK, (char*) &nodelack,
+        sizeof (int));
+    errno_assert (rc != SOCKET_ERROR);
+#endif
+
     //  Create the engine object for this connection.
     tcp_engine_t *engine = new (std::nothrow) tcp_engine_t (fd, options);
     alloc_assert (engine);