Background

Knative Serving is configured by two ways. By global configuration on KnativeServing resource, and by per-service configuration. Per-service configuration is partially described by autoscalling doc (1). Global configuration isn't described.

Expectation

Configuration of KnativeServing resource should be described in Configuring Serverless subsection, and linked in installing Knative Serving doc (2), to instruct users on configuration options they have.

We should describe all parameters of KnativeServing resource that users may be changing.

There are some upstream docs on this (3) that we might reuse.

(1) https://docs.openshift.com/container-platform/4.3/serverless/knative_serving/configuring-knative-serving-autoscaling.html
(2) https://docs.openshift.com/container-platform/4.3/serverless/installing_serverless/installing-knative-serving.html
(3) https://knative.dev/docs/serving/configuring-autoscaling/