Merge "Avoid redundant call to update_resource_stats from RT"

nova/compute/resource_tracker.py

@@ -713,7 +713,8 @@ class ResourceTracker(object):
         """Check to see if any resources have changed."""
         nodename = compute_node.hypervisor_hostname
         old_compute = self.old_resources[nodename]
-        if not obj_base.obj_equal_prims(compute_node, old_compute):
+        if not obj_base.obj_equal_prims(
+                compute_node, old_compute, ['updated_at']):
             self.old_resources[nodename] = copy.deepcopy(compute_node)
             return True
         return False

nova/tests/unit/compute/test_resource_tracker.py

@@ -1099,6 +1099,26 @@ class TestUpdateComputeNode(BaseTestCase):
         self.rt._update(mock.sentinel.ctx, new_compute)
         self.assertFalse(urs_mock.called)
 
+    @mock.patch('nova.objects.Service.get_by_compute_host')
+    def test_existing_compute_node_updated_diff_updated_at(self, service_mock):
+        self._setup_rt()
+        ts1 = timeutils.utcnow()
+        ts2 = ts1 + datetime.timedelta(seconds=10)
+
+        orig_compute = _COMPUTE_NODE_FIXTURES[0].obj_clone()
+        orig_compute.updated_at = ts1
+        self.rt.compute_nodes[_NODENAME] = orig_compute
+        self.rt.old_resources[_NODENAME] = orig_compute
+
+        # Make the new_compute object have a different timestamp
+        # from orig_compute.
+        new_compute = orig_compute.obj_clone()
+        new_compute.updated_at = ts2
+
+        urs_mock = self.sched_client_mock.update_resource_stats
+        self.rt._update(mock.sentinel.ctx, new_compute)
+        self.assertFalse(urs_mock.called)
+
     @mock.patch('nova.objects.Service.get_by_compute_host')
     def test_existing_compute_node_updated_new_resources(self, service_mock):
         self._setup_rt()