// cleanupUnhealthyReplicas will scale down old rcs with unhealthy replicas, so that all unhealthy replicas will be deleted.
func (dc *DeploymentController) cleanupUnhealthyReplicas(oldRCs []*api.ReplicationController, deployment extensions.Deployment, maxCleanupCount int) (int, error) {
sort.Sort(controller.ControllersByCreationTimestamp(oldRCs))
// Safely scale down all old rcs with unhealthy replicas. ReplicationController/ReplicaSet will sort the pods in the order
// such that not-ready < ready, unscheduled < scheduled, and pending < running. This ensures that unhealthy replicas will
// been deleted first and won't increase unavailability.
totalScaledDown := 0
for _, targetRC := range oldRCs {
if totalScaledDown >= maxCleanupCount {
break
}
if targetRC.Spec.Replicas == 0 {
// cannot scale down this RC.
continue
}
readyPodCount, err := deploymentutil.GetAvailablePodsForRCs(dc.client, []*api.ReplicationController{targetRC}, 0)
if err != nil {
return totalScaledDown, fmt.Errorf("could not find available pods: %v", err)
}
if targetRC.Spec.Replicas == readyPodCount {
// no unhealthy replicas found, no scaling required.
continue
}
scaledDownCount := int(math.Min(float64(maxCleanupCount-totalScaledDown), float64(targetRC.Spec.Replicas-readyPodCount)))
newReplicasCount := targetRC.Spec.Replicas - scaledDownCount
_, err = dc.scaleRCAndRecordEvent(targetRC, newReplicasCount, deployment)
if err != nil {
return totalScaledDown, err
}
totalScaledDown += scaledDownCount
}
return totalScaledDown, nil
}
// scaleDownOldRCsForRollingUpdate scales down old rcs when deployment strategy is "RollingUpdate".
// Need check maxUnavailable to ensure availability
func (dc *DeploymentController) scaleDownOldRCsForRollingUpdate(allRCs []*api.ReplicationController, oldRCs []*api.ReplicationController, deployment extensions.Deployment) (int, error) {
maxUnavailable, isPercent, err := util.GetIntOrPercentValue(&deployment.Spec.Strategy.RollingUpdate.MaxUnavailable)
if err != nil {
return 0, fmt.Errorf("invalid value for MaxUnavailable: %v", err)
}
if isPercent {
maxUnavailable = util.GetValueFromPercent(maxUnavailable, deployment.Spec.Replicas)
}
// Check if we can scale down.
minAvailable := deployment.Spec.Replicas - maxUnavailable
minReadySeconds := deployment.Spec.MinReadySeconds
// Find the number of ready pods.
readyPodCount, err := deploymentutil.GetAvailablePodsForRCs(dc.client, allRCs, minReadySeconds)
if err != nil {
return 0, fmt.Errorf("could not find available pods: %v", err)
}
if readyPodCount <= minAvailable {
// Cannot scale down.
return 0, nil
}
sort.Sort(controller.ControllersByCreationTimestamp(oldRCs))
totalScaledDown := 0
totalScaleDownCount := readyPodCount - minAvailable
for _, targetRC := range oldRCs {
if totalScaledDown >= totalScaleDownCount {
// No further scaling required.
break
}
if targetRC.Spec.Replicas == 0 {
// cannot scale down this RC.
continue
}
// Scale down.
scaleDownCount := int(math.Min(float64(targetRC.Spec.Replicas), float64(totalScaleDownCount-totalScaledDown)))
newReplicasCount := targetRC.Spec.Replicas - scaleDownCount
_, err = dc.scaleRCAndRecordEvent(targetRC, newReplicasCount, deployment)
if err != nil {
return totalScaledDown, err
}
totalScaledDown += scaleDownCount
}
return totalScaledDown, nil
}
func (dc *DeploymentController) cleanupOldRcs(oldRCs []*api.ReplicationController, deployment extensions.Deployment) error {
diff := len(oldRCs) - *deployment.Spec.RevisionHistoryLimit
if diff <= 0 {
return nil
}
sort.Sort(controller.ControllersByCreationTimestamp(oldRCs))
var errList []error
// TODO: This should be parallelized.
for i := 0; i < diff; i++ {
controller := oldRCs[i]
// Avoid delete rc with non-zero replica counts
if controller.Spec.Replicas != 0 || controller.Generation > controller.Status.ObservedGeneration {
continue
}
if err := dc.client.ReplicationControllers(controller.Namespace).Delete(controller.Name); err != nil && !errors.IsNotFound(err) {
glog.V(2).Infof("Failed deleting old rc %v for deployment %v: %v", controller.Name, deployment.Name, err)
errList = append(errList, err)
}
}
return utilerrors.NewAggregate(errList)
}