diff --git a/cinder/volume/throttling.py b/cinder/volume/throttling.py
index 21c19956e16..b8ce5705ab0 100644
--- a/cinder/volume/throttling.py
+++ b/cinder/volume/throttling.py
@@ -90,7 +90,7 @@ class BlkioCgroup(Throttle):
 
     def _set_limits(self, rw, devs):
         total = sum(devs.values())
-        for dev in devs:
+        for dev in sorted(devs):
             self._limit_bps(rw, dev, self.bps_limit * devs[dev] / total)
 
     @utils.synchronized('BlkioCgroup')
diff --git a/tox.ini b/tox.ini
index 720d1449275..d86012f2008 100644
--- a/tox.ini
+++ b/tox.ini
@@ -103,6 +103,7 @@ commands =
     cinder.tests.unit.test_volume_configuration \
     cinder.tests.unit.test_volume_glance_metadata \
     cinder.tests.unit.test_volume_rpcapi \
+    cinder.tests.unit.test_volume_throttling \
     cinder.tests.unit.test_volume_transfer \
     cinder.tests.unit.test_volume_types \
     cinder.tests.unit.test_volume_types_extra_specs \