diff --git a/tuned/monitors/base.py b/tuned/monitors/base.py
index ee21837..26400aa 100644
--- a/tuned/monitors/base.py
+++ b/tuned/monitors/base.py
@@ -16,14 +16,14 @@ class Monitor(object):
 
 	# class properties
 
-	_class_initialized = False
-	_instances = set()
-	_available_devices = set()
-	_updating_devices = set()
-	_load = {}
-
 	@classmethod
 	def _init_class(cls):
+		cls._class_initialized = False
+		cls._instances = set()
+		cls._available_devices = set()
+		cls._updating_devices = set()
+		cls._load = {}
+
 		cls._init_available_devices()
 		assert(type(cls._available_devices) is set)
 		cls._class_initialized = True
@@ -52,9 +52,9 @@ class Monitor(object):
 	# instance properties
 
 	def __init__(self, devices = None):
-		if self._class_initialized is False:
+		if not hasattr(self, "_class_initialized"):
 			self._init_class()
-			assert(self._class_initialized)
+			assert hasattr(self, "_class_initialized")
 
 		if devices is not None:
 			self.devices = devices
diff --git a/tuned/monitors/repository.py b/tuned/monitors/repository.py
index 542c8a7..4462c5b 100644
--- a/tuned/monitors/repository.py
+++ b/tuned/monitors/repository.py
@@ -25,5 +25,5 @@ class MonitorRepository(tuned.patterns.Singleton):
 
 	def update(self):
 		for monitor in self._monitors:
-			log.debug("updating %s")
+			log.debug("updating %s" % monitor)
 			monitor.update()