voctocore: controlserver: skip on_loop/on_write when nothing to do

This reduces voctocore CPU usage quite a bit.

1 files changed, 17 insertions, 13 deletions

diff --git a/voctocore/lib/controlserver.py b/voctocore/lib/controlserver.py
index b0fe3d5..c0ceb0b 100644
--- a/voctocore/lib/controlserver.py
+++ b/voctocore/lib/controlserver.py
@@ -17,13 +17,10 @@ class ControlServer(TCPMultiConnection):
 
 		self.commands = ControlServerCommands(pipeline)
 
-		GObject.idle_add(self.on_loop)
-
 	def on_accepted(self, conn, addr):
 		'''Asynchronous connection listener. Starts a handler for each connection.'''
 		self.log.debug('setting gobject io-watch on connection')
 		GObject.io_add_watch(conn, GObject.IO_IN, self.on_data, [''])
-		GObject.io_add_watch(conn, GObject.IO_OUT, self.on_write)
 
 	def on_data(self, conn, _, leftovers, *args):
 		'''Asynchronous connection handler. Pushes data from socket
@@ -59,6 +56,8 @@ class ControlServer(TCPMultiConnection):
 				self.close_connection(conn)
 				return False
 
+			if self.command_queue.empty():
+				GObject.idle_add(self.on_loop)
 			self.command_queue.put((line, conn))
 
 		if close_after:
@@ -75,12 +74,12 @@ class ControlServer(TCPMultiConnection):
 		'''Command handler. Processes commands in the command queue whenever
 		nothing else is happening (registered as GObject idle callback)'''
 		if self.command_queue.empty():
-			return True
+			return False
 		line, requestor = self.command_queue.get()
 
 		words = line.split()
 		if len(words) < 1:
-			return True
+			return False
 
 		command = words[0]
 		args = words[1:]
@@ -115,17 +114,22 @@ class ControlServer(TCPMultiConnection):
 				if isinstance(responseObject, list):
 					for obj in responseObject:
 						signal = "%s\n" % str(obj)
-						for conn, queue in self.currentConnections.items():
-							queue.put(signal)
-
+						for conn in self.currentConnections:
+							self._schedule_write(conn, signal)
 				else:
 					response = "%s\n" % str(responseObject)
 
 		finally:
 			if response is not None and requestor in self.currentConnections:
-				self.currentConnections[requestor].put(response)
+				self._schedule_write(requestor, response)
 
-		return True
+		return False
+
+	def _schedule_write(self, conn, message):
+		queue = self.currentConnections[conn]
+		if queue.empty():
+			GObject.io_add_watch(conn, GObject.IO_OUT, self.on_write)
+		queue.put(message)
 
 	def on_write(self, conn, *args):
 		# TODO: on_loop() is not called as soon as there is a writable socket
@@ -137,7 +141,7 @@ class ControlServer(TCPMultiConnection):
 			return False
 
 		if queue.empty():
-			return True
+			return False
 
 		message = queue.get()
 		try:
@@ -152,7 +156,7 @@ class ControlServer(TCPMultiConnection):
 			words = msg.split()
 			words[-1] = self.commands.encodeSourceName(int(words[-1]))
 			msg = " ".join(words) + '\n'
-			for queue in self.currentConnections.values():
-				queue.put(msg)
+			for conn in self.currentConnections:
+				self._schedule_write(conn, msg)
 		except Exception as e:
 			self.log.debug("error during notify: %s", e)