# HG changeset patch
# User Valentin Bartenev <vbart@nginx.com>
# Date 1416599509 -10800
# Node ID 7ea6f5140ed97b7c0f903819395240628bfc7538
# Parent  0395f788b080ba6c45246ffbdeed72c86d417731
SPDY: push pending data while closing a stream as with keepalive.

This helps to avoid delays in sending the last chunk of data because
of bad interaction between Nagle's algorithm on nginx side and
delayed ACK on the client side.

Delays could also be caused by TCP_CORK/TCP_NOPUSH if SPDY was
working without SSL and sendfile() was used.

diff --git a/src/http/ngx_http_spdy.c b/src/http/ngx_http_spdy.c
--- a/src/http/ngx_http_spdy.c
+++ b/src/http/ngx_http_spdy.c
@@ -3156,8 +3156,10 @@ ngx_http_spdy_close_stream_handler(ngx_e
 void
 ngx_http_spdy_close_stream(ngx_http_spdy_stream_t *stream, ngx_int_t rc)
 {
+    int                           tcp_nodelay;
     ngx_event_t                  *ev;
-    ngx_connection_t             *fc;
+    ngx_connection_t             *c, *fc;
+    ngx_http_core_loc_conf_t     *clcf;
     ngx_http_spdy_stream_t      **index, *s;
     ngx_http_spdy_srv_conf_t     *sscf;
     ngx_http_spdy_connection_t   *sc;
@@ -3183,6 +3185,54 @@ ngx_http_spdy_close_stream(ngx_http_spdy
         {
             sc->connection->error = 1;
         }
+
+    } else {
+        c = sc->connection;
+
+        if (c->tcp_nopush == NGX_TCP_NOPUSH_SET) {
+            if (ngx_tcp_push(c->fd) == -1) {
+                ngx_connection_error(c, ngx_socket_errno,
+                                     ngx_tcp_push_n " failed");
+                c->error = 1;
+                tcp_nodelay = 0;
+
+            } else {
+                c->tcp_nopush = NGX_TCP_NOPUSH_UNSET;
+                tcp_nodelay = ngx_tcp_nodelay_and_tcp_nopush ? 1 : 0;
+            }
+
+        } else {
+            tcp_nodelay = 1;
+        }
+
+        clcf = ngx_http_get_module_loc_conf(stream->request,
+                                            ngx_http_core_module);
+
+        if (tcp_nodelay
+            && clcf->tcp_nodelay
+            && c->tcp_nodelay == NGX_TCP_NODELAY_UNSET)
+        {
+            ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "tcp_nodelay");
+
+            if (setsockopt(c->fd, IPPROTO_TCP, TCP_NODELAY,
+                           (const void *) &tcp_nodelay, sizeof(int))
+                == -1)
+            {
+#if (NGX_SOLARIS)
+                /* Solaris returns EINVAL if a socket has been shut down */
+                c->log_error = NGX_ERROR_IGNORE_EINVAL;
+#endif
+
+                ngx_connection_error(c, ngx_socket_errno,
+                                     "setsockopt(TCP_NODELAY) failed");
+
+                c->log_error = NGX_ERROR_INFO;
+                c->error = 1;
+
+            } else {
+                c->tcp_nodelay = NGX_TCP_NODELAY_SET;
+            }
+        }
     }
 
     if (sc->stream == stream) {