Merge "Convert percent metrics back into the [0, 1] range"

nova/compute/monitors/cpu/virt_driver.py

@@ -77,17 +77,20 @@ class Monitor(base.CPUMonitorBase):
                           + stats["idle"] + stats["iowait"])
         cputime = float(stats["total"] - self._cpu_stats.get("total", 0))
 
+        # NOTE(jwcroppe): Convert all the `perc` values to their integer forms
+        # since pre-conversion their values are within the range [0, 1] and the
+        # objects.MonitorMetric.value field requires an integer.
         perc = (stats["user"] - self._cpu_stats.get("user", 0)) / cputime
-        self._data["cpu.user.percent"] = perc
+        self._data["cpu.user.percent"] = int(perc * 100)
 
         perc = (stats["kernel"] - self._cpu_stats.get("kernel", 0)) / cputime
-        self._data["cpu.kernel.percent"] = perc
+        self._data["cpu.kernel.percent"] = int(perc * 100)
 
         perc = (stats["idle"] - self._cpu_stats.get("idle", 0)) / cputime
-        self._data["cpu.idle.percent"] = perc
+        self._data["cpu.idle.percent"] = int(perc * 100)
 
         perc = (stats["iowait"] - self._cpu_stats.get("iowait", 0)) / cputime
-        self._data["cpu.iowait.percent"] = perc
+        self._data["cpu.iowait.percent"] = int(perc * 100)
 
         # Compute the current system-wide CPU utilization as a percentage.
         used = stats["user"] + stats["kernel"] + stats["iowait"]
@@ -95,6 +98,6 @@ class Monitor(base.CPUMonitorBase):
                      + self._cpu_stats.get("kernel", 0)
                      + self._cpu_stats.get("iowait", 0))
         perc = (used - prev_used) / cputime
-        self._data["cpu.percent"] = perc
+        self._data["cpu.percent"] = int(perc * 100)
 
         self._cpu_stats = stats.copy()

nova/objects/monitor_metric.py

@@ -17,6 +17,16 @@ from nova.objects import fields
 from nova import utils
 
 
+# NOTE(jwcroppe): Used to determine which fields whose value we need to adjust
+# (read: divide by 100.0) before sending information to the RPC notifier since
+# these values were expected to be within the range [0, 1].
+FIELDS_REQUIRING_CONVERSION = [fields.MonitorMetricType.CPU_USER_PERCENT,
+                               fields.MonitorMetricType.CPU_KERNEL_PERCENT,
+                               fields.MonitorMetricType.CPU_IDLE_PERCENT,
+                               fields.MonitorMetricType.CPU_IOWAIT_PERCENT,
+                               fields.MonitorMetricType.CPU_PERCENT]
+
+
 @base.NovaObjectRegistry.register
 class MonitorMetric(base.NovaObject):
     # Version 1.0: Initial version
@@ -54,7 +64,10 @@ class MonitorMetric(base.NovaObject):
         }
 
         if self.obj_attr_is_set('value'):
-            dict_to_return['value'] = self.value
+            if self.name in FIELDS_REQUIRING_CONVERSION:
+                dict_to_return['value'] = self.value / 100.0
+            else:
+                dict_to_return['value'] = self.value
         elif self.obj_attr_is_set('numa_membw_values'):
             dict_to_return['numa_membw_values'] = self.numa_membw_values
 

nova/tests/unit/compute/monitors/cpu/test_virt_driver.py

@@ -65,13 +65,8 @@ class VirtDriverCPUMonitorTestCase(test.NoDBTestCase):
         self.assertEqual(metrics["cpu.kernel.time"], 5664160000000)
         self.assertEqual(metrics["cpu.idle.time"], 1592705190000000)
         self.assertEqual(metrics["cpu.iowait.time"], 6121490000000)
-        self.assertTrue(metrics["cpu.user.percent"] <= 1
-                        and metrics["cpu.user.percent"] >= 0)
-        self.assertTrue(metrics["cpu.kernel.percent"] <= 1
-                        and metrics["cpu.kernel.percent"] >= 0)
-        self.assertTrue(metrics["cpu.idle.percent"] <= 1
-                        and metrics["cpu.idle.percent"] >= 0)
-        self.assertTrue(metrics["cpu.iowait.percent"] <= 1
-                        and metrics["cpu.iowait.percent"] >= 0)
-        self.assertTrue(metrics["cpu.percent"] <= 1
-                        and metrics["cpu.percent"] >= 0)
+        self.assertEqual(metrics["cpu.user.percent"], 1)
+        self.assertEqual(metrics["cpu.kernel.percent"], 0)
+        self.assertEqual(metrics["cpu.idle.percent"], 97)
+        self.assertEqual(metrics["cpu.iowait.percent"], 0)
+        self.assertEqual(metrics["cpu.percent"], 2)

nova/tests/unit/objects/test_monitor_metric.py

@@ -25,6 +25,13 @@ _monitor_metric_spec = {
     'source': 'nova.virt.libvirt.driver'
 }
 
+_monitor_metric_perc_spec = {
+    'name': fields.MonitorMetricType.CPU_PERCENT,
+    'value': 0.17,
+    'timestamp': timeutils.strtime(_ts_now),
+    'source': 'nova.virt.libvirt.driver'
+}
+
 _monitor_numa_metric_spec = {
     'name': fields.MonitorMetricType.NUMA_MEM_BW_CURRENT,
     'numa_membw_values': {"0": 10, "1": 43},
@@ -43,6 +50,14 @@ class _TestMonitorMetricObject(object):
                                     source='nova.virt.libvirt.driver')
         self.assertEqual(_monitor_metric_spec, obj.to_dict())
 
+    def test_monitor_metric_perc_to_dict(self):
+        """Test to ensure division by 100.0 occurs on percentage value."""
+        obj = objects.MonitorMetric(name='cpu.percent',
+                                    value=17,
+                                    timestamp=_ts_now,
+                                    source='nova.virt.libvirt.driver')
+        self.assertEqual(_monitor_metric_perc_spec, obj.to_dict())
+
     def test_monitor_metric_list_to_list(self):
         obj = objects.MonitorMetric(name='cpu.frequency',
                                     value=1000,