kubernetes - Replicaset-controller なぜ burstReplicas が必要なのか

Question

kubernetesの自己修復機能について勉強しています。rsc.burstReplicas の意味を知りたい

func (rsc *ReplicaSetController) manageReplicas(filteredPods []*v1.Pod, rs *apps.ReplicaSet) error {
    diff := len(filteredPods) - int(*(rs.Spec.Replicas))
    rsKey, err := controller.KeyFunc(rs)
    if err != nil {
        utilruntime.HandleError(fmt.Errorf("Couldn't get key for %v %#v: %v", rsc.Kind, rs, err))
        return nil
    }
    if diff < 0 {
        diff *= -1
        if diff > rsc.burstReplicas {
            diff = rsc.burstReplicas
        }
~~~