Merge "Add debug message to report calculated metric for workload_balance"

watcher/decision_engine/strategy/strategies/workload_balance.py

@@ -192,15 +192,30 @@ class WorkloadBalance(base.WorkloadStabilizationBaseStrategy):
             if (free_res['vcpu'] >= required_cores and
                     free_res['memory'] >= required_mem and
                     free_res['disk'] >= required_disk):
-                if (self._meter == 'instance_cpu_usage' and
-                    ((src_instance_workload + workload) <
-                     self.threshold / 100 * host.vcpus)):
-                    destination_hosts.append(instance_data)
-                if (self._meter == 'instance_ram_usage' and
-                    ((src_instance_workload + workload) <
-                     self.threshold / 100 * host.memory)):
-                    destination_hosts.append(instance_data)
-
+                if self._meter == 'instance_cpu_usage':
+                    usage = src_instance_workload + workload
+                    usage_percent = usage / host.vcpus * 100
+                    limit = self.threshold / 100 * host.vcpus
+                    if usage < limit:
+                        destination_hosts.append(instance_data)
+                    LOG.debug(f"Host {host.hostname} evaluated as destination "
+                              f"for {instance_to_migrate.uuid}. Host usage "
+                              f"for cpu would be {usage_percent}."
+                              f"The threshold is: {self.threshold}. "
+                              f"selected: {usage < limit}"
+                              )
+                if self._meter == 'instance_ram_usage':
+                    usage = src_instance_workload + workload
+                    usage_percent = usage / host.memory * 100
+                    limit = self.threshold / 100 * host.memory
+                    if usage < limit:
+                        destination_hosts.append(instance_data)
+                    LOG.debug(f"Host {host.hostname} evaluated as destination "
+                              f"for {instance_to_migrate.uuid}. Host usage "
+                              f"for ram would be {usage_percent}."
+                              f"The threshold is: {self.threshold}. "
+                              f"selected: {usage < limit}"
+                              )
         return destination_hosts
 
     def group_hosts_by_cpu_or_ram_util(self):
@@ -251,8 +266,10 @@ class WorkloadBalance(base.WorkloadStabilizationBaseStrategy):
             cluster_workload += node_workload
             if self._meter == 'instance_cpu_usage':
                 node_util = node_workload / node.vcpus * 100
+                host_metric = 'host_cpu_usage_percent'
             else:
                 node_util = node_workload / node.memory * 100
+                host_metric = 'host_ram_usage_percent'
 
             instance_data = {
                 'compute_node': node, self._meter: node_util,
@@ -262,6 +279,9 @@ class WorkloadBalance(base.WorkloadStabilizationBaseStrategy):
                 overload_hosts.append(instance_data)
             else:
                 nonoverload_hosts.append(instance_data)
+            LOG.debug(f"Host usage for {node_id}: {host_metric} is "
+                      f"{node_util}. Higher than threshold {self.threshold}: "
+                      f"{node_util >= self.threshold}")
 
         avg_workload = 0
         if cluster_size != 0:

watcher/tests/decision_engine/model/gnocchi_metrics.py

@@ -304,8 +304,8 @@ class FakeGnocchiMetrics(object):
         mock = {}
 
         # node 0
-        mock['INSTANCE_1'] = 30
-        mock['73b09e16-35b7-4922-804e-e8f5d9b740fc'] = 12
+        mock['INSTANCE_1'] = 40
+        mock['73b09e16-35b7-4922-804e-e8f5d9b740fc'] = 9
         # node 1
         mock['INSTANCE_3'] = 12
         mock['INSTANCE_4'] = 12

watcher/tests/decision_engine/strategy/strategies/test_workload_balance.py

@@ -22,6 +22,7 @@ from unittest import mock
 from watcher.applier.loading import default
 from watcher.common import utils
 from watcher.decision_engine.strategy import strategies
+from watcher.decision_engine.strategy.strategies import workload_balance
 from watcher.tests.decision_engine.model import gnocchi_metrics
 from watcher.tests.decision_engine.strategy.strategies.test_base \
     import TestBaseStrategy
@@ -77,7 +78,7 @@ class TestWorkloadBalance(TestBaseStrategy):
         n1, n2, avg, w_map = self.strategy.group_hosts_by_cpu_or_ram_util()
         self.assertEqual(n1[0]['compute_node'].uuid, 'Node_0')
         self.assertEqual(n2[0]['compute_node'].uuid, 'Node_1')
-        self.assertEqual(avg, 33.0)
+        self.assertEqual(avg, 36.5)
 
     def test_choose_instance_to_migrate(self):
         model = self.fake_c_cluster.generate_scenario_6_with_2_nodes()
@@ -99,7 +100,8 @@ class TestWorkloadBalance(TestBaseStrategy):
             n1, avg, w_map)
         self.assertIsNone(instance_to_mig)
 
-    def test_filter_destination_hosts(self):
+    @mock.patch.object(workload_balance.LOG, 'debug', autospec=True)
+    def test_filter_destination_hosts_cpu(self, mock_debug):
         model = self.fake_c_cluster.generate_scenario_6_with_2_nodes()
         self.m_c_model.return_value = model
         self.strategy.datasource = mock.MagicMock(
@@ -111,6 +113,42 @@ class TestWorkloadBalance(TestBaseStrategy):
             n2, instance_to_mig[1], avg, w_map)
         self.assertEqual(len(dest_hosts), 1)
         self.assertEqual(dest_hosts[0]['compute_node'].uuid, 'Node_1')
+        expected_calls = [
+            mock.call('Host usage for Node_0: host_cpu_usage_percent is 32.5. '
+                      'Higher than threshold 25.0: True'),
+            mock.call('Host usage for Node_1: host_cpu_usage_percent is 7.5. '
+                      'Higher than threshold 25.0: False'),
+            mock.call('Host hostname_1 evaluated as destination for '
+                      '73b09e16-35b7-4922-804e-e8f5d9b740fc. Host usage for '
+                      'cpu would be 20.0.The threshold is: 25.0. selected: '
+                      'True')]
+        mock_debug.assert_has_calls(expected_calls, any_order=True)
+
+    @mock.patch.object(workload_balance.LOG, 'debug', autospec=True)
+    def test_filter_destination_hosts_ram(self, mock_debug):
+        model = self.fake_c_cluster.generate_scenario_6_with_2_nodes()
+        self.m_c_model.return_value = model
+        self.strategy._meter = 'instance_ram_usage'
+        self.strategy.threshold = 30.0
+        self.strategy.datasource = mock.MagicMock(
+            statistic_aggregation=self.fake_metrics.mock_get_statistics_wb)
+        n1, n2, avg, w_map = self.strategy.group_hosts_by_cpu_or_ram_util()
+        instance_to_mig = self.strategy.choose_instance_to_migrate(
+            n1, avg, w_map)
+        dest_hosts = self.strategy.filter_destination_hosts(
+            n2, instance_to_mig[1], avg, w_map)
+        self.assertEqual(len(dest_hosts), 1)
+        self.assertEqual(dest_hosts[0]['compute_node'].uuid, 'Node_1')
+        expected_calls = [
+            mock.call('Host usage for Node_0: host_ram_usage_percent is '
+                      '37.121212121212125. Higher than threshold 30.0: True'),
+            mock.call('Host usage for Node_1: host_ram_usage_percent is '
+                      '18.181818181818183. Higher than threshold 30.0: False'),
+            mock.call('Host hostname_1 evaluated as destination for '
+                      '73b09e16-35b7-4922-804e-e8f5d9b740fc. Host usage for '
+                      'ram would be 25.0.The threshold is: 30.0. selected: '
+                      'True')]
+        mock_debug.assert_has_calls(expected_calls, any_order=True)
 
     def test_execute_no_workload(self):
         model = self.fake_c_cluster.\