[core] disable Nagle algorithm (TCP_NODELAY)

disable Nagle algorithm (TCP_NODELAY) on client sockets

src/connections.c

@@ -909,6 +909,9 @@ connection *connection_accept(server *srv, server_socket *srv_socket) {
 		}
 		return NULL;
 	} else {
+		if (cnt_addr.plain.sa_family != AF_UNIX) {
+			network_accept_tcp_nagle_disable(cnt);
+		}
 		return connection_accepted(srv, srv_socket, &cnt_addr, cnt);
 	}
 }

src/network.c

@@ -50,6 +50,28 @@ static void ssl_info_callback(const SSL *ssl, int where, int ret) {
 }
 #endif
 
+void
+network_accept_tcp_nagle_disable (const int fd)
+{
+    static int noinherit_tcpnodelay = -1;
+    int opt;
+
+    if (!noinherit_tcpnodelay) /* TCP_NODELAY inherited from listen socket */
+        return;
+
+    if (noinherit_tcpnodelay < 0) {
+        socklen_t optlen = sizeof(opt);
+        if (0 == getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen)) {
+            noinherit_tcpnodelay = !opt;
+            if (opt)           /* TCP_NODELAY inherited from listen socket */
+                return;
+        }
+    }
+
+    opt = 1;
+    (void)setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof(opt));
+}
+
 static handler_t network_server_handle_fdevent(server *srv, void *context, int revents) {
 	server_socket *srv_socket = (server_socket *)context;
 	connection *con;
@@ -408,6 +430,14 @@ static int network_server_init(server *srv, buffer *host_token, specific_config
 		goto error_free_socket;
 	}
 
+	if (srv_socket->addr.plain.sa_family != AF_UNIX) {
+		val = 1;
+		if (setsockopt(srv_socket->fd, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val)) < 0) {
+			log_error_write(srv, __FILE__, __LINE__, "ss", "socketsockopt(TCP_NODELAY) failed:", strerror(errno));
+			goto error_free_socket;
+		}
+	}
+
 	if (0 != bind(srv_socket->fd, (struct sockaddr *) &(srv_socket->addr), addr_len)) {
 		switch(srv_socket->addr.plain.sa_family) {
 		case AF_UNIX:

src/network.h

@@ -4,6 +4,8 @@
 
 #include "server.h"
 
+void network_accept_tcp_nagle_disable(int fd);
+
 int network_write_chunkqueue(server *srv, connection *con, chunkqueue *c, off_t max_bytes);
 
 int network_init(server *srv);

src/server.c

@@ -530,6 +530,10 @@ static int server_oneshot_init(server *srv, int fd) {
 		return 0;
 	}
 
+	if (cnt_addr.plain.sa_family != AF_UNIX) {
+		network_accept_tcp_nagle_disable(fd);
+	}
+
 	con = connection_accepted(srv, srv_socket, &cnt_addr, fd);
 	if (NULL == con) return 0;