Reduce apiserver metrics cardinality of non-core APIs

* Reduce `apiserver_request_duration_seconds_count` cardinality
by dropping series for non-core Kubernetes APIs. This is done
to match `apiserver_request_duration_seconds_count` relabeling
* These two relabels must be performed the same way to avoid
affecting new SLO calculations (upcoming)
* See https://github.com/kubernetes-monitoring/kubernetes-mixin/issues/498

Related: https://github.com/poseidon/typhoon/pull/596

CHANGES.md

@@ -4,6 +4,12 @@ Notable changes between versions.
 
 ## Latest
 
+### Addons
+
+* Reduce apiserver metrics cardinality for non-core APIs ([#830](https://github.com/poseidon/typhoon/pull/830))
+
+## v1.19.1
+
 * Kubernetes [v1.19.1](https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.19.md#v1191)
   * Change control plane seccomp annotations to GA `seccompProfile` ([#822](https://github.com/poseidon/typhoon/pull/822))
 * Update Cilium from v1.8.2 to [v1.8.3](https://github.com/cilium/cilium/releases/tag/v1.8.3)

addons/prometheus/config.yaml

@@ -68,6 +68,9 @@ data:
       - source_labels: [__name__, group]
         regex: apiserver_request_duration_seconds_bucket;.+
         action: drop
+      - source_labels: [__name__, group]
+        regex: apiserver_request_duration_seconds_count;.+
+        action: drop
 
     # Scrape config for node (i.e. kubelet) /metrics (e.g. 'kubelet_'). Explore
     # metrics from a node by scraping kubelet (127.0.0.1:10250/metrics).