diff --git a/test.cfg b/test.cfg
index c0c757e..2eaf762 100644
--- a/test.cfg
+++ b/test.cfg
@@ -72,3 +72,7 @@ merge=1
 [my_broken_plugin]
 type=broken
 
+[my_disk_plugin]
+type=disk
+
+
diff --git a/tuned/monitors/monitor_disk.py b/tuned/monitors/monitor_disk.py
index e7ceeb2..fe01749 100644
--- a/tuned/monitors/monitor_disk.py
+++ b/tuned/monitors/monitor_disk.py
@@ -11,6 +11,13 @@ class DiskMonitor(tuned.monitors.Monitor):
 		available = set(filter(cls._is_device_supported, block_devices))
 		cls._available_devices = available
 
+		for d in available:
+			cls._load[d] = {}
+			cls._load[d]["new"] = ['0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0']
+			cls._load[d]["max"] = [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
+			cls._update_disk(d)
+			cls._load[d]["max"] = [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
+
 	@classmethod
 	def _is_device_supported(cls, device):
 		vendor_file = "/sys/block/%s/device/vendor" % device
@@ -24,9 +31,26 @@ class DiskMonitor(tuned.monitors.Monitor):
 	@classmethod
 	def update(cls):
 		for device in cls._updating_devices:
-			# TODO
-			cls._load[device] = None
+			cls._update_disk(device)
+
 
 	@classmethod
-	def _update_disk(cls, name):
-		pass
+	def _update_disk(cls, dev):
+		l = open("/sys/block/"+dev+"/stat", "r").read()
+		cls._load[dev]["old"] = cls._load[dev]["new"]
+		cls._load[dev]["new"] = l.split()
+		l = cls._calcdiff(dev)
+		for i in xrange(len(l)):
+			if l[i] > cls._load[dev]["max"][i]:
+				cls._load[dev]["max"][i] = l[i]
+
+		cls._load[dev]['diff'] = cls._calcdiff(dev)
+		cls._load[dev]["READ"] = float(cls._load[dev]["diff"][1]) / float(cls._load[dev]["max"][1])
+		cls._load[dev]["WRITE"] = float(cls._load[dev]["diff"][5]) / float(cls._load[dev]["max"][5])
+
+	@classmethod
+	def _calcdiff(cls, dev):
+		l = []
+		for i in xrange(len(cls._load[dev]["old"])):
+			l.append(int(cls._load[dev]["new"][i]) - int(cls._load[dev]["old"][i]))
+		return l
diff --git a/tuned/monitors/repository.py b/tuned/monitors/repository.py
index 72c1246..846cd7d 100644
--- a/tuned/monitors/repository.py
+++ b/tuned/monitors/repository.py
@@ -14,6 +14,12 @@ class MonitorRepository(tuned.patterns.Singleton):
 		log.debug("creating monitor %s" % plugin_name)
 		# TODO: exception handling
 		monitor_cls = self._loader.load(plugin_name)
+
+		for monitor in self._monitors:
+			if (isinstance(monitor, monitor_cls) and 
+				(monitor.devices == devices or devices == None)):
+				return monitor
+
 		monitor_instance = monitor_cls(devices)
 		self._monitors.add(monitor_instance)
 		return monitor_instance
diff --git a/tuned/plugins/plugin_disk.py b/tuned/plugins/plugin_disk.py
new file mode 100644
index 0000000..210417e
--- /dev/null
+++ b/tuned/plugins/plugin_disk.py
@@ -0,0 +1,84 @@
+import os, copy
+import tuned.plugins
+import tuned.logs
+import tuned.monitors
+import struct
+
+log = tuned.logs.get()
+
+class DiskPlugin(tuned.plugins.Plugin):
+
+	_supported_vendors = ["ATA", "SCSI"]
+
+	def __init__(self, devices, options):
+		"""
+		"""
+		super(self.__class__, self).__init__(None, options)
+
+		self.devidle = {}
+		self.power = ["255", "225", "195", "165", "145", "125", "105", "85", "70", "55", "30", "20"]
+		self.spindown = ["0", "250", "230", "210", "190", "170", "150", "130", "110", "90", "70", "60"]
+		self.levels = len(self.power)
+
+		self._load_monitor = tuned.monitors.get_repository().create("disk", devices)
+
+	@classmethod
+	def tunable_devices(cls):
+		block_devices = os.listdir("/sys/block")
+		available = set(filter(cls._is_device_supported, block_devices))
+		cls._available_devices = available
+
+	@classmethod
+	def _is_device_supported(cls, device):
+		vendor_file = "/sys/block/%s/device/vendor" % device
+		try:
+			vendor = open(vendor_file).read().strip()
+		except IOError:
+			return False
+
+		return vendor in cls._supported_vendors
+
+	def _updateIdle(self, dev, devload):
+		idle = self.devidle.setdefault(dev, {})
+		idle.setdefault("LEVEL", 0)
+		for type in ("READ", "WRITE"):
+			if devload[type] == 0.0:
+				idle.setdefault(type, 0)
+				idle[type] += 1
+			else:
+				idle.setdefault(type, 0)
+				idle[type] = 0
+
+
+	def cleanup(self):
+		log.debug("Cleanup")
+
+		for dev in self.devidle.keys():
+			if self.devidle[dev]["LEVEL"] > 0:
+				os.system("hdparm -S0 -B255 /dev/"+dev+" > /dev/null 2>&1")
+
+	def update_tuning(self):
+		load = self._load_monitor.get_load()
+		for dev, devload in load.iteritems():
+			self._updateIdle(dev, devload)
+
+			if self.devidle[dev]["LEVEL"] < self.levels-1 and self.devidle[dev]["READ"] >= 6 and self.devidle[dev]["WRITE"] >= 6:
+				self.devidle[dev].setdefault("LEVEL", 0)
+				self.devidle[dev]["LEVEL"] += 1
+				level = self.devidle[dev]["LEVEL"]
+
+				log.debug("Level changed to %d (power %s, spindown %s)" % (level, self.power[level], self.spindown[level]))
+				os.system("hdparm -S"+self.power[level]+" -B"+self.spindown[level]+" /dev/"+dev+" > /dev/null 2>&1")
+
+			if self.devidle[dev]["LEVEL"] > 0 and (self.devidle[dev]["READ"] == 0 or self.devidle[dev]["WRITE"] == 0):
+				self.devidle[dev].setdefault("LEVEL", 0)
+				self.devidle[dev]["LEVEL"] -= 2
+				if self.devidle[dev]["LEVEL"] < 0:
+					self.devidle[dev]["LEVEL"] = 0
+				level = self.devidle[dev]["LEVEL"]
+
+				log.debug("Level changed to %d (power %s, spindown %s)" % (level, self.power[level], self.spindown[level]))
+				os.system("hdparm -S"+self.power[level]+" -B"+self.spindown[level]+" /dev/"+dev+" > /dev/null 2>&1")
+
+			log.debug("%s load: read %f, write %f" % (dev, load[dev]["READ"], load[dev]["WRITE"]))
+			log.debug("%s idle: read %d, write %d, level %d" % (dev, self.devidle[dev]["READ"], self.devidle[dev]["WRITE"], self.devidle[dev]["LEVEL"]))
diff --git a/tuned/plugins/plugin_net.py b/tuned/plugins/plugin_net.py
index 85a6819..adf2975 100644
--- a/tuned/plugins/plugin_net.py
+++ b/tuned/plugins/plugin_net.py
@@ -49,7 +49,6 @@ class NetTuningPlugin(tuned.plugins.Plugin):
 		load = self._load_monitor.get_load()
 		for dev, devload in load.iteritems():
 			self._updateIdle(dev, devload)
-			print self.devidle
 			if self.devidle[dev]["LEVEL"] == 0 and self.devidle[dev]["READ"] >= 6 and self.devidle[dev]["WRITE"] >= 6:
 				self.devidle[dev]["LEVEL"] = 1