[change] Changed default alert tolerances to reduce noise

Author: nemesifier

docs/user/alerts.rst

@@ -18,8 +18,9 @@ setting includes:
   - **Less than**: triggers when the value is below the threshold.
 
 - **Threshold**: the metric value that triggers the alert.
-- **Tolerance**: the duration (in minutes) for which the threshold must be
-  breached before an alert is triggered.
+- **Tolerance**: the duration (in minutes) the threshold must be
+  continuously breached before triggering an alert. Helps reduce noise
+  from flapping metrics.
 
 OpenWISP Monitoring provides built-in alerts for the following metrics:
 
@@ -42,7 +43,7 @@ enabled by default.
 ========= =================
 Operator  ``< (less than)``
 Threshold ``1``
-Tolerance ``0`` minutes
+Tolerance ``30`` minutes
 ========= =================
 
 .. note::
@@ -63,7 +64,7 @@ specified time. This alert is enabled by default.
 ========= =================
 Operator  ``< (less than)``
 Threshold ``1``
-Tolerance ``5`` minutes
+Tolerance ``10`` minutes
 ========= =================
 
 .. note::
@@ -103,7 +104,7 @@ default.
 ========= ====================
 Operator  ``> (greater than)``
 Threshold ``90`` (percent)
-Tolerance ``5`` minutes
+Tolerance ``30`` minutes
 ========= ====================
 
 Memory Usage
@@ -117,7 +118,7 @@ default.
 ========= ====================
 Operator  ``> (greater than)``
 Threshold ``95`` (percent)
-Tolerance ``5`` minutes
+Tolerance ``30`` minutes
 ========= ====================
 
 Disk Usage

openwisp_monitoring/device/tests/test_admin.py

@@ -657,7 +657,7 @@ def _assert_alertsettings_inline_in_response(response):
             )
             self.assertContains(
                 response,
-                'metric-content_type-object_id-0-alertsettings-0-custom_tolerance" value="0"',
+                'metric-content_type-object_id-0-alertsettings-0-custom_tolerance" value="30"',
             )
 
         with self.subTest(

openwisp_monitoring/monitoring/configuration.py

@@ -118,7 +118,7 @@ def _get_access_tech():
                 "query": chart_query["rtt"],
             },
         },
-        "alert_settings": {"operator": "<", "threshold": 1, "tolerance": 0},
+        "alert_settings": {"operator": "<", "threshold": 1, "tolerance": 30},
         "notification": {
             "problem": {
                 "verbose_name": "Ping PROBLEM",
@@ -151,7 +151,7 @@ def _get_access_tech():
         "name": "Configuration Applied",
         "key": "config_applied",
         "field_name": "config_applied",
-        "alert_settings": {"operator": "<", "threshold": 1, "tolerance": 5},
+        "alert_settings": {"operator": "<", "threshold": 1, "tolerance": 10},
         "notification": {
             "problem": {
                 "verbose_name": "Configuration Applied PROBLEM",
@@ -481,7 +481,7 @@ def _get_access_tech():
                 "query": chart_query["memory"],
             }
         },
-        "alert_settings": {"operator": ">", "threshold": 95, "tolerance": 5},
+        "alert_settings": {"operator": ">", "threshold": 95, "tolerance": 30},
         "notification": {
             "problem": {
                 "verbose_name": "Memory usage PROBLEM",
@@ -531,7 +531,7 @@ def _get_access_tech():
                 "query": chart_query["cpu"],
             }
         },
-        "alert_settings": {"operator": ">", "threshold": 90, "tolerance": 5},
+        "alert_settings": {"operator": ">", "threshold": 90, "tolerance": 30},
         "notification": {
             "problem": {
                 "verbose_name": "CPU usage PROBLEM",

openwisp_monitoring/monitoring/tests/test_admin.py

@@ -30,7 +30,7 @@ def test_alert_settings_inline(self):
         self.assertEqual(r.status_code, 200)
         self.assertContains(r, '<option value="&lt;" selected>less than</option>')
         self.assertContains(r, 'name="alertsettings-0-custom_threshold" value="1"')
-        self.assertContains(r, 'name="alertsettings-0-custom_tolerance" value="0"')
+        self.assertContains(r, 'name="alertsettings-0-custom_tolerance" value="30"')
 
     def test_admin_menu_groups(self):
         # Test menu group (openwisp-utils menu group) for Metric and Check models