Enable default polling interval override

By default collectd polling interval is set to 10 seconds for all plugins,
which is bringing down the entire cloud if the default Gnocchi deployment
(Swift on controllers) is used. We have to override the default higher value.

Closes-Bug: #1771083
Change-Id: I210c72028da35068ed8469b2d2deb75797a2b08f

puppet/services/metrics/collectd.yaml

@@ -37,6 +37,14 @@ parameters:
     type: string
     description: Keystone region for endpoint
     default: 'regionOne'
+  CollectdDefaultPollingInterval:
+    default: 120
+    type: number
+    description: >
+      Controls how often registered read functions are called and with that
+      the resolution of the collected data. This value can be overriden per
+      plugin(per role) by setting "::collectd::plugin::<plugin_name>::interval"
+      key in ExtraConfig(<role_name>ExtraConfig).
   CollectdDefaultPlugins:
     default:
       - disk
@@ -217,6 +225,7 @@ outputs:
             collectd::minimum_version: "5.7"
             collectd::plugin::unixsock::socketgroup: root
             collectd::plugin::unixsock::socketfile: /var/run/collectd-socket
+            collectd::interval: {get_param: CollectdDefaultPollingInterval}
             tripleo.collectd.plugins.collectd:
               yaql:
                 data:

releasenotes/notes/collectd-polling-4aac123faaebd1bc.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    Adds possibility to override default polling interval for collectd and set
+    default value to 120 seconds, because current default (10s)
+    was too aggressive.