From 014604812e65d325316778ac98ac7c422226fce8 Mon Sep 17 00:00:00 2001
From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
Date: Sat, 7 Apr 2018 02:58:10 +0200
Subject: [PATCH] When doing persistent connections, explicitly flush the
 socket so that we do not get 200 ms extra delay for the last bytes due to
 TCP_CORK.

---
 server.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/server.cpp b/server.cpp
index e9bc654..a7f579c 100644
--- a/server.cpp
+++ b/server.cpp
@@ -1,6 +1,7 @@
 #include <assert.h>
 #include <errno.h>
 #include <netinet/in.h>
+#include <netinet/tcp.h>
 #include <pthread.h>
 #include <stdint.h>
 #include <stdio.h>
@@ -1247,6 +1248,14 @@ bool Server::more_requests(Client *client)
 	// Log to access_log.
 	access_log->write(client->get_stats());
 
+	// Flush pending data; does not cancel out TCP_CORK (since that still takes priority),
+	// but does a one-off flush.
+	int one = 1;
+	if (setsockopt(client->sock, SOL_TCP, TCP_NODELAY, &one, sizeof(one)) == -1) {
+		log_perror("setsockopt(TCP_NODELAY)");
+		// Can still continue.
+	}
+
 	// Switch states and reset the parsers. We don't reset statistics.
 	client->state = Client::READING_REQUEST;
 	client->url.clear();
-- 
2.39.2