diff --git a/neutron/plugins/nicira/vshield/tasks/tasks.py b/neutron/plugins/nicira/vshield/tasks/tasks.py
index 77f233ae53..4a901f3106 100755
--- a/neutron/plugins/nicira/vshield/tasks/tasks.py
+++ b/neutron/plugins/nicira/vshield/tasks/tasks.py
@@ -20,7 +20,6 @@ import uuid
 
 from eventlet import event
 from eventlet import greenthread
-from eventlet.support import greenlets as greenlet
 
 from neutron.common import exceptions
 from neutron.openstack.common import log as logging
@@ -295,12 +294,9 @@ class TaskManager():
         while True:
             try:
                 if self._stopped:
-                    # Somehow greenlet.GreenletExit exception is ignored
-                    # during unit-test when self._execute() is making db
-                    # access. This makes this thread not terminating and
-                    # stop() caller wait indefinitely. So we added a check
-                    # here before trying to do a block call on getting a
-                    # task from queue
+                    # Gracefully terminate this thread if the _stopped
+                    # attribute was set to true
+                    LOG.info(_("Stopping TaskManager"))
                     break
 
                 # get a task from queue, or timeout for periodic status check
@@ -324,17 +320,11 @@ class TaskManager():
                         self._result(task)
                     else:
                         self._enqueue(task)
-            except greenlet.GreenletExit:
-                break
             except Exception:
-                LOG.exception(_("TaskManager terminated"))
+                LOG.exception(_("TaskManager terminating because "
+                                "of an exception"))
                 break
 
-        self._monitor.stop()
-        if self._monitor_busy:
-            self._monitor.wait()
-        self._abort()
-
     def add(self, task):
         task.id = uuid.uuid1()
         self._tasks_queue.append(task)
@@ -347,8 +337,13 @@ class TaskManager():
             return
         self._stopped = True
         self._thread.kill()
-        self._thread.wait()
         self._thread = None
+        # Stop looping call and abort running tasks
+        self._monitor.stop()
+        if self._monitor_busy:
+            self._monitor.wait()
+        self._abort()
+        LOG.info(_("TaskManager terminated"))
 
     def has_pending_task(self):
         if self._tasks_queue or self._tasks or self._main_thread_exec_task:
diff --git a/neutron/tests/unit/nicira/test_edge_router.py b/neutron/tests/unit/nicira/test_edge_router.py
index ca2d2a33af..2d1adc192c 100644
--- a/neutron/tests/unit/nicira/test_edge_router.py
+++ b/neutron/tests/unit/nicira/test_edge_router.py
@@ -144,7 +144,8 @@ class ServiceRouterTest(test_nicira_plugin.NiciraL3NatTest,
             manager.show_pending_tasks()
             raise Exception(_("Tasks not completed"))
         manager.stop()
-
+        # Ensure the manager thread has been stopped
+        self.assertIsNone(manager._thread)
         super(ServiceRouterTest, self).tearDown()
 
     def _create_router(self, fmt, tenant_id, name=None,
diff --git a/neutron/tests/unit/nicira/test_vcns_driver.py b/neutron/tests/unit/nicira/test_vcns_driver.py
index ddc0c339e4..952fdff971 100644
--- a/neutron/tests/unit/nicira/test_vcns_driver.py
+++ b/neutron/tests/unit/nicira/test_vcns_driver.py
@@ -45,6 +45,9 @@ class VcnsDriverTaskManagerTestCase(base.BaseTestCase):
 
     def tearDown(self):
         self.manager.stop()
+        # Task manager should not leave running threads around
+        # if _thread is None it means it was killed in stop()
+        self.assertIsNone(self.manager._thread)
         super(VcnsDriverTaskManagerTestCase, self).tearDown()
 
     def _test_task_manager_task_process_state(self, sync_exec=False):
@@ -222,6 +225,9 @@ class VcnsDriverTaskManagerTestCase(base.BaseTestCase):
 
         manager = ts.TaskManager().start(100)
         manager.stop()
+        # Task manager should not leave running threads around
+        # if _thread is None it means it was killed in stop()
+        self.assertIsNone(manager._thread)
         manager.start(100)
 
         alltasks = {}
@@ -236,6 +242,9 @@ class VcnsDriverTaskManagerTestCase(base.BaseTestCase):
 
         greenthread.sleep(stop_wait)
         manager.stop()
+        # Task manager should not leave running threads around
+        # if _thread is None it means it was killed in stop()
+        self.assertIsNone(manager._thread)
 
         for res, tasks in alltasks.iteritems():
             for task in tasks:
@@ -325,6 +334,9 @@ class VcnsDriverTestCase(base.BaseTestCase):
 
     def tearDown(self):
         self.vcns_driver.task_manager.stop()
+        # Task manager should not leave running threads around
+        # if _thread is None it means it was killed in stop()
+        self.assertIsNone(self.vcns_driver.task_manager._thread)
         super(VcnsDriverTestCase, self).tearDown()
 
     def _deploy_edge(self):