maxUnavailableNum, err := intstr.GetScaledValueFromIntOrPercent(intstr.ValueOrDefault(maxUnavailable, intstr.FromInt32(1)), replicaCount, false)
	if err != nil {
		return 0, err
	}
	// maxUnavailable might be zero for small percentage with round down.
	// So we have to enforce it not to be less than 1.
	if maxUnavailableNum < 1 {
		maxUnavailableNum = 1
	}
	return maxUnavailableNum, nil