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kubernetesetcdkubernetes-operator

How many CRs (Custom Resources) can a kubernetes cluster handle?

  1. How many CRs of a certain CRD can a k8s cluster handle?
  2. How many CRs can a certain controller (or Operator) reconcile?

Thanks!

Solution

  • 1. How many CRs of a certain CRD can a k8s cluster handle?

    As many as your API server's storage space allows:

    Custom resources consume storage space in the same way that ConfigMaps do. Creating too many custom resources may overload your API server's storage space.

    Aggregated API servers may use the same storage as the main API server, in which case the same warning applies.

    2. How many CRs can a certain controller (or Operator) reconcile?

    A controller in Kubernetes keeps track of at least one resource type. There many built-in controllers in Kubernetes, replication controller, namespace controller, service account controller, etc. Custom Resource definition along with Custom Controller makes the Operator Pattern. It's hard to tell what is the maximum CR that a given Operator could handle as it would depend on different aspects such as the Operator itself. For example, this guide shows that the Binary Provisioning Agent (BPA) Custom Controller can handle two or more custom resources.

    You can find some useful sources below: