Dedicated thread for keepalives

nano/lib/stats_enums.hpp

@@ -70,6 +70,7 @@ enum class detail : uint8_t
 	ok,
 	loop,
 	loop_cleanup,
+	loop_keepalive,
 	total,
 	process,
 	processed,

nano/lib/thread_roles.cpp

@@ -112,6 +112,9 @@ std::string nano::thread_role::get_string (nano::thread_role::name role)
 		case nano::thread_role::name::network_cleanup:
 			thread_role_name_string = "Net cleanup";
 			break;
+		case nano::thread_role::name::network_keepalive:
+			thread_role_name_string = "Net keepalive";
+			break;
 		default:
 			debug_assert (false && "nano::thread_role::get_string unhandled thread role");
 	}

nano/lib/thread_roles.hpp

@@ -46,6 +46,7 @@ enum class name
 	local_block_broadcasting,
 	rep_tiers,
 	network_cleanup,
+	network_keepalive,
 };
 
 /*

nano/node/network.cpp

@@ -34,6 +34,7 @@ nano::network::~network ()
 	// All threads must be stopped before this destructor
 	debug_assert (processing_threads.empty ());
 	debug_assert (!cleanup_thread.joinable ());
+	debug_assert (!keepalive_thread.joinable ());
 }
 
 void nano::network::start ()
@@ -43,7 +44,10 @@ void nano::network::start ()
 		run_cleanup ();
 	});
 
-	ongoing_keepalive ();
+	keepalive_thread = std::thread ([this] () {
+		nano::thread_role::set (nano::thread_role::name::network_keepalive);
+		run_keepalive ();
+	});
 
 	if (!node.flags.disable_tcp_realtime)
 	{
@@ -77,6 +81,10 @@ void nano::network::stop ()
 	}
 	processing_threads.clear ();
 
+	if (keepalive_thread.joinable ())
+	{
+		keepalive_thread.join ();
+	}
 	if (cleanup_thread.joinable ())
 	{
 		cleanup_thread.join ();
@@ -142,6 +150,28 @@ void nano::network::run_cleanup ()
 	}
 }
 
+void nano::network::run_keepalive ()
+{
+	nano::unique_lock<nano::mutex> lock{ mutex };
+	while (!stopped)
+	{
+		condition.wait_for (lock, node.network_params.network.keepalive_period);
+		lock.unlock ();
+
+		if (stopped)
+		{
+			return;
+		}
+
+		node.stats.inc (nano::stat::type::network, nano::stat::detail::loop_keepalive);
+
+		flood_keepalive (0.75f);
+		flood_keepalive_self (0.25f);
+
+		lock.lock ();
+	}
+}
+
 void nano::network::send_keepalive (std::shared_ptr<nano::transport::channel> const & channel_a)
 {
 	nano::keepalive message{ node.network_params.network };
@@ -536,19 +566,6 @@ void nano::network::cleanup (std::chrono::steady_clock::time_point const & cutof
 	}
 }
 
-void nano::network::ongoing_keepalive ()
-{
-	flood_keepalive (0.75f);
-	flood_keepalive_self (0.25f);
-	std::weak_ptr<nano::node> node_w (node.shared ());
-	node.workers.add_timed_task (std::chrono::steady_clock::now () + node.network_params.network.keepalive_period, [node_w] () {
-		if (auto node_l = node_w.lock ())
-		{
-			node_l->network.ongoing_keepalive ();
-		}
-	});
-}
-
 std::size_t nano::network::size () const
 {
 	return tcp_channels.size ();

nano/node/network.hpp

@@ -114,7 +114,6 @@ class network final
 	nano::tcp_endpoint bootstrap_peer ();
 	nano::endpoint endpoint () const;
 	void cleanup (std::chrono::steady_clock::time_point const & cutoff);
-	void ongoing_keepalive ();
 	std::size_t size () const;
 	float size_sqrt () const;
 	bool empty () const;
@@ -132,6 +131,7 @@ class network final
 private:
 	void run_processing ();
 	void run_cleanup ();
+	void run_keepalive ();
 	void process_message (nano::message const &, std::shared_ptr<nano::transport::channel> const &);
 
 private: // Dependencies
@@ -158,6 +158,7 @@ class network final
 	nano::condition_variable condition;
 	std::vector<boost::thread> processing_threads; // Using boost::thread to enable increased stack size
 	std::thread cleanup_thread;
+	std::thread keepalive_thread;
 
 public:
 	static unsigned const broadcast_interval_ms = 10;