buildman: initialize queuemetrics asynchronously

buildman/server.py

@@ -93,13 +93,8 @@ class BuilderServer(object):
     logger.debug('Starting server on port %s, with controller on port %s', websocket_port,
                  controller_port)
 
-    TASKS = [
-      Task(self._initialize(loop, host, websocket_port, controller_port, ssl)),
-      Task(self._queue_metrics_updater()),
-    ]
-
     try:
-      loop.run_until_complete(trollius.wait(TASKS))
+      loop.run_until_complete(self._initialize(loop, host, websocket_port, controller_port, ssl))
     except KeyboardInterrupt:
       pass
     finally:
@@ -195,6 +190,7 @@ class BuilderServer(object):
 
   @trollius.coroutine
   def _queue_metrics_updater(self):
+    logger.debug('Initializing queue metrics updater')
     while self._current_status == BuildServerStatus.RUNNING:
       yield From(trollius.sleep(30))
       logger.debug('Writing metrics')
@@ -212,5 +208,8 @@ class BuilderServer(object):
     create_wsgi_server(self._controller_app, loop=loop, host=host, port=controller_port, ssl=ssl)
     yield From(loop.create_server(transport_factory, host, websocket_port, ssl=ssl))
 
+    # Initialize the metrics updater
+    trollius.async(self._queue_metrics_updater())
+
     # Initialize the work queue checker.
     yield From(self._work_checker())