Add OLMConfig / disabling copied CSVs

Author: adellape

_topic_maps/_topic_map.yml

@@ -1324,6 +1324,9 @@ Topics:
   - Name: Deleting Operators from a cluster
     File: olm-deleting-operators-from-cluster
     Distros: openshift-enterprise,openshift-origin
+  - Name: Configuring OLM features
+    File: olm-config
+    Distros: openshift-enterprise,openshift-origin
   - Name: Configuring proxy support
     File: olm-configuring-proxy-support
     Distros: openshift-enterprise,openshift-origin

modules/olm-disabling-copied-csvs.adoc

@@ -0,0 +1,49 @@
+// Module included in the following assemblies:
+//
+// * operators/admin/olm-config.adoc
+
+:_content-type: PROCEDURE
+[id="olm-disabling-copied-csvs_{context}"]
+= Disabling copied CSVs
+
+When an Operator is installed by Operator Lifecycle Manager (OLM), a simplified copy of its cluster service version (CSV) is created in every namespace that the Operator is configured to watch. These CSVs are known as _copied CSVs_ and communicate to users which controllers are actively reconciling resource events in a given namespace.
+
+When Operators are configured to use the `AllNamespaces` install mode, versus targeting a single or specified set of namespaces, a copied CSV is created in every namespace on the cluster. On especially large clusters, with namespaces and installed Operators potentially in the hundreds or thousands, copied CSVs consume an untenable amount of resources, such as OLM's memory usage, cluster etcd limits, and networking.
+
+To support these larger clusters, cluster administrators can disable copied CSVs for Operators installed with the `AllNamespaces` mode.
+
+.Procedure
+
+* Edit the `OLMConfig` object named `cluster` and set the `spec.features.disableCopiedCSVs` field to `true`:
++
+[source,terminal]
+----
+$ oc apply -f - <<EOF
+apiVersion: operators.coreos.com/v1
+kind: OLMConfig
+metadata:
+  name: cluster
+spec:
+  features:
+    disableCopiedCSVs: true <1>
+EOF
+----
+<1> Disabled copied CSVs for `AllNamespaces` install mode Operators
+
+.Verification
+
+* When copied CSVs are disabled, OLM captures this information in an event in the Operator's namespace:
++
+[source,terminal]
+----
+$ oc get events
+----
++
+.Example output
+[source,terminal]
+----
+LAST SEEN   TYPE      REASON               OBJECT                                MESSAGE
+85s         Warning   DisabledCopiedCSVs   clusterserviceversion/my-csv.v1.0.0   CSV copying disabled for operators/my-csv.v1.0.0
+----
++
+When the `spec.features.disableCopiedCSVs` field is missing or set to `false`, OLM recreates the copied CSVs for all Operators installed with the `AllNamespaces` mode and deletes the previously mentioned events.

operators/admin/olm-config.adoc

@@ -0,0 +1,16 @@
+:_content-type: ASSEMBLY
+[id="olm-config"]
+= Configuring Operator Lifecycle Manager features
+include::modules/common-attributes.adoc[]
+:context: olm-config
+
+toc::[]
+
+The Operator Lifecycle Manager (OLM) controller is configured by an `OLMConfig` custom resource (CR) named `cluster`. Cluster administrators can modify this resource to enable or disable certain features.
+
+This document outlines the features currently supported by OLM that are configured by the `OLMConfig` resource.
+
+include::modules/olm-disabling-copied-csvs.adoc[leveloffset=+1]
+.Additional resources
+
+* xref:../../operators/understanding/olm/olm-understanding-operatorgroups.adoc#olm-operatorgroups-membership_olm-understanding-operatorgroups[Install modes]