The queries per second (QPS) and burst values determine the frequency of requests or API calls to the API server.

Configuring burst and QPS values for net-kourier

The queries per second (QPS) value determines the number of client requests or API calls that are sent to the API server.

The burst value determines how many requests from the client can be stored for processing. Requests exceeding this buffer will be dropped. This is helpful for controllers that are bursty and do not spread their requests uniformly in time.

When the net-kourier-controller restarts, it parses all ingress resources deployed on the cluster, which leads to a significant number of API calls. Due to this, the net-kourier-controller can take a long time to start.

You can adjust the QPS and burst values for the net-kourier-controller in the KnativeServing CR:

KnativeServing CR example
apiVersion: operator.knative.dev/v1beta1
kind: KnativeServing
  name: knative-serving
  namespace: knative-serving
  - name: net-kourier-controller
    - container: controller
      - name: KUBE_API_BURST
        value: "200" (1)
      - name: KUBE_API_QPS
        value: "200" (2)
1 The QPS rate of communication between controller and the API Server. The default value is 200.
2 The burst capacity of communication between Kubelet and the API Server. The default value is 200.