Configuring Activator capacity

If there is more than one Activator in the system, Knative puts as many Activators on the request path as required to handle the current request load plus the target burst capacity. If the target burst capacity is 0, Knative only puts the Activator into the request path if the Revision is scaled to zero.

Knative uses at least two Activators to enable high availability if possible. The actual number of Activators is calculated taking the Activator capacity into account, by using the formula (replicas * target + target-burst-capacity)/activator-capacity. This means that there are enough Activators in the routing path to handle the theoretical capacity of the existing application, including any additional target burst capacity.

Setting the Activator capacity

• Global key: activator-capacity
• Possible values: int (at least 1)
• Default: 100

Example:

Global (ConfigMap)

apiVersion: v1
kind: ConfigMap
metadata:
  name: config-autoscaler
  namespace: knative-serving
data:
  activator-capacity: "200"

Global (Operator)

apiVersion: operator.knative.dev/v1alpha1
kind: KnativeServing
metadata:
  name: knative-serving
spec:
  config:
    autoscaler:
      activator-capacity: "200"