// NewRSNewReplicas calculates the number of replicas a deployment's new RS should have.
// When one of the followings is true, we're rolling out the deployment; otherwise, we're scaling it.
// 1) The new RS is saturated: newRS's replicas == deployment's replicas
// 2) Max number of pods allowed is reached: deployment's replicas + maxSurge == all RSs' replicas
func NewRSNewReplicas(deployment *extensions.Deployment, allRSs []*extensions.ReplicaSet, newRS *extensions.ReplicaSet) (int32, error) {
switch deployment.Spec.Strategy.Type {
case extensions.RollingUpdateDeploymentStrategyType:
// Check if we can scale up.
maxSurge, err := intstrutil.GetValueFromIntOrPercent(&deployment.Spec.Strategy.RollingUpdate.MaxSurge, int(deployment.Spec.Replicas), true)
if err != nil {
return 0, err
}
// Find the total number of pods
currentPodCount := GetReplicaCountForReplicaSets(allRSs)
maxTotalPods := deployment.Spec.Replicas + int32(maxSurge)
if currentPodCount >= maxTotalPods {
// Cannot scale up.
return newRS.Spec.Replicas, nil
}
// Scale up.
scaleUpCount := maxTotalPods - currentPodCount
// Do not exceed the number of desired replicas.
scaleUpCount = int32(integer.IntMin(int(scaleUpCount), int(deployment.Spec.Replicas-newRS.Spec.Replicas)))
return newRS.Spec.Replicas + scaleUpCount, nil
case extensions.RecreateDeploymentStrategyType:
return deployment.Spec.Replicas, nil
default:
return 0, fmt.Errorf("deployment type %v isn't supported", deployment.Spec.Strategy.Type)
}
}
// cleanupUnhealthyReplicas will scale down old replica sets with unhealthy replicas, so that all unhealthy replicas will be deleted.
func (dc *DeploymentController) cleanupUnhealthyReplicas(oldRSs []*extensions.ReplicaSet, deployment *extensions.Deployment, maxCleanupCount int32) ([]*extensions.ReplicaSet, int32, error) {
sort.Sort(controller.ReplicaSetsByCreationTimestamp(oldRSs))
// Safely scale down all old replica sets with unhealthy replicas. Replica set 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 := int32(0)
for i, targetRS := range oldRSs {
if totalScaledDown >= maxCleanupCount {
break
}
if targetRS.Spec.Replicas == 0 {
// cannot scale down this replica set.
continue
}
glog.V(4).Infof("Found %d available pods in old RS %s/%s", targetRS.Status.AvailableReplicas, targetRS.Namespace, targetRS.Name)
if targetRS.Spec.Replicas == targetRS.Status.AvailableReplicas {
// no unhealthy replicas found, no scaling required.
continue
}
scaledDownCount := int32(integer.IntMin(int(maxCleanupCount-totalScaledDown), int(targetRS.Spec.Replicas-targetRS.Status.AvailableReplicas)))
newReplicasCount := targetRS.Spec.Replicas - scaledDownCount
if newReplicasCount > targetRS.Spec.Replicas {
return nil, 0, fmt.Errorf("when cleaning up unhealthy replicas, got invalid request to scale down %s/%s %d -> %d", targetRS.Namespace, targetRS.Name, targetRS.Spec.Replicas, newReplicasCount)
}
_, updatedOldRS, err := dc.scaleReplicaSetAndRecordEvent(targetRS, newReplicasCount, deployment)
if err != nil {
return nil, totalScaledDown, err
}
totalScaledDown += scaledDownCount
oldRSs[i] = updatedOldRS
}
return oldRSs, totalScaledDown, nil
}
// cleanupUnhealthyReplicas will scale down old replica sets with unhealthy replicas, so that all unhealthy replicas will be deleted.
func (dc *DeploymentController) cleanupUnhealthyReplicas(oldRSs []*extensions.ReplicaSet, deployment extensions.Deployment, maxCleanupCount int) (int, error) {
sort.Sort(controller.ReplicaSetsByCreationTimestamp(oldRSs))
// Safely scale down all old replica sets with unhealthy replicas. Replica set 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 _, targetRS := range oldRSs {
if totalScaledDown >= maxCleanupCount {
break
}
if targetRS.Spec.Replicas == 0 {
// cannot scale down this replica set.
continue
}
readyPodCount, err := deploymentutil.GetAvailablePodsForReplicaSets(dc.client, []*extensions.ReplicaSet{targetRS}, 0)
if err != nil {
return totalScaledDown, fmt.Errorf("could not find available pods: %v", err)
}
if targetRS.Spec.Replicas == readyPodCount {
// no unhealthy replicas found, no scaling required.
continue
}
scaledDownCount := integer.IntMin(maxCleanupCount-totalScaledDown, targetRS.Spec.Replicas-readyPodCount)
newReplicasCount := targetRS.Spec.Replicas - scaledDownCount
_, _, err = dc.scaleReplicaSetAndRecordEvent(targetRS, newReplicasCount, deployment)
if err != nil {
return totalScaledDown, err
}
totalScaledDown += scaledDownCount
}
return totalScaledDown, nil
}
func (dc *DeploymentController) reconcileNewReplicaSet(allRSs []*extensions.ReplicaSet, newRS *extensions.ReplicaSet, deployment extensions.Deployment) (bool, error) {
if newRS.Spec.Replicas == deployment.Spec.Replicas {
// Scaling not required.
return false, nil
}
if newRS.Spec.Replicas > deployment.Spec.Replicas {
// Scale down.
_, err := dc.scaleReplicaSetAndRecordEvent(newRS, deployment.Spec.Replicas, deployment)
return true, err
}
// Check if we can scale up.
maxSurge, err := intstrutil.GetValueFromIntOrPercent(&deployment.Spec.Strategy.RollingUpdate.MaxSurge, deployment.Spec.Replicas)
if err != nil {
return false, err
}
// Find the total number of pods
currentPodCount := deploymentutil.GetReplicaCountForReplicaSets(allRSs)
maxTotalPods := deployment.Spec.Replicas + maxSurge
if currentPodCount >= maxTotalPods {
// Cannot scale up.
return false, nil
}
// Scale up.
scaleUpCount := maxTotalPods - currentPodCount
// Do not exceed the number of desired replicas.
scaleUpCount = integer.IntMin(scaleUpCount, deployment.Spec.Replicas-newRS.Spec.Replicas)
newReplicasCount := newRS.Spec.Replicas + scaleUpCount
_, err = dc.scaleReplicaSetAndRecordEvent(newRS, newReplicasCount, deployment)
return true, err
}
// scaleDownOldReplicaSetsForRollingUpdate scales down old replica sets when deployment strategy is "RollingUpdate".
// Need check maxUnavailable to ensure availability
func (dc *DeploymentController) scaleDownOldReplicaSetsForRollingUpdate(allRSs []*extensions.ReplicaSet, oldRSs []*extensions.ReplicaSet, 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.GetAvailablePodsForReplicaSets(dc.client, allRSs, 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.ReplicaSetsByCreationTimestamp(oldRSs))
totalScaledDown := 0
totalScaleDownCount := readyPodCount - minAvailable
for _, targetRS := range oldRSs {
if totalScaledDown >= totalScaleDownCount {
// No further scaling required.
break
}
if targetRS.Spec.Replicas == 0 {
// cannot scale down this ReplicaSet.
continue
}
// Scale down.
scaleDownCount := integer.IntMin(targetRS.Spec.Replicas, totalScaleDownCount-totalScaledDown)
newReplicasCount := targetRS.Spec.Replicas - scaleDownCount
_, err = dc.scaleReplicaSetAndRecordEvent(targetRS, newReplicasCount, deployment)
if err != nil {
return totalScaledDown, err
}
totalScaledDown += scaleDownCount
}
return totalScaledDown, nil
}
// scaleDownOldReplicaSetsForRollingUpdate scales down old replica sets when deployment strategy is "RollingUpdate".
// Need check maxUnavailable to ensure availability
func (dc *DeploymentController) scaleDownOldReplicaSetsForRollingUpdate(allRSs []*extensions.ReplicaSet, oldRSs []*extensions.ReplicaSet, deployment *extensions.Deployment) (int32, error) {
maxUnavailable := deploymentutil.MaxUnavailable(*deployment)
// Check if we can scale down.
minAvailable := deployment.Spec.Replicas - maxUnavailable
minReadySeconds := deployment.Spec.MinReadySeconds
// Find the number of ready pods.
// TODO: use dc.getAvailablePodsForReplicaSets instead
availablePodCount, err := deploymentutil.GetAvailablePodsForReplicaSets(dc.client, deployment, allRSs, minReadySeconds)
if err != nil {
return 0, fmt.Errorf("could not find available pods: %v", err)
}
if availablePodCount <= minAvailable {
// Cannot scale down.
return 0, nil
}
glog.V(4).Infof("Found %d available pods in deployment %s, scaling down old RSes", availablePodCount, deployment.Name)
sort.Sort(controller.ReplicaSetsByCreationTimestamp(oldRSs))
totalScaledDown := int32(0)
totalScaleDownCount := availablePodCount - minAvailable
for _, targetRS := range oldRSs {
if totalScaledDown >= totalScaleDownCount {
// No further scaling required.
break
}
if targetRS.Spec.Replicas == 0 {
// cannot scale down this ReplicaSet.
continue
}
// Scale down.
scaleDownCount := int32(integer.IntMin(int(targetRS.Spec.Replicas), int(totalScaleDownCount-totalScaledDown)))
newReplicasCount := targetRS.Spec.Replicas - scaleDownCount
if newReplicasCount > targetRS.Spec.Replicas {
return 0, fmt.Errorf("when scaling down old RS, got invalid request to scale down %s/%s %d -> %d", targetRS.Namespace, targetRS.Name, targetRS.Spec.Replicas, newReplicasCount)
}
_, _, err = dc.scaleReplicaSetAndRecordEvent(targetRS, newReplicasCount, deployment)
if err != nil {
return totalScaledDown, err
}
totalScaledDown += scaleDownCount
}
return totalScaledDown, nil
}
func isLess(i, j reflect.Value) (bool, error) {
switch i.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
return i.Int() < j.Int(), nil
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
return i.Uint() < j.Uint(), nil
case reflect.Float32, reflect.Float64:
return i.Float() < j.Float(), nil
case reflect.String:
return i.String() < j.String(), nil
case reflect.Ptr:
return isLess(i.Elem(), j.Elem())
case reflect.Struct:
// sort unversioned.Time
in := i.Interface()
if t, ok := in.(unversioned.Time); ok {
return t.Before(j.Interface().(unversioned.Time)), nil
}
// fallback to the fields comparison
for idx := 0; idx < i.NumField(); idx++ {
less, err := isLess(i.Field(idx), j.Field(idx))
if err != nil || !less {
return less, err
}
}
return true, nil
case reflect.Array, reflect.Slice:
// note: the length of i and j may be different
for idx := 0; idx < integer.IntMin(i.Len(), j.Len()); idx++ {
less, err := isLess(i.Index(idx), j.Index(idx))
if err != nil || !less {
return less, err
}
}
return true, nil
default:
return false, fmt.Errorf("unsortable type: %v", i.Kind())
}
}
func isLess(i, j reflect.Value) (bool, error) {
switch i.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
return i.Int() < j.Int(), nil
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
return i.Uint() < j.Uint(), nil
case reflect.Float32, reflect.Float64:
return i.Float() < j.Float(), nil
case reflect.String:
return i.String() < j.String(), nil
case reflect.Ptr:
return isLess(i.Elem(), j.Elem())
case reflect.Struct:
// special case handling
lessFuncList := []structLessFunc{timeLess}
if ok, less := structLess(i, j, lessFuncList); ok {
return less, nil
}
// fallback to the fields comparision
for idx := 0; idx < i.NumField(); idx++ {
less, err := isLess(i.Field(idx), j.Field(idx))
if err != nil || !less {
return less, err
}
}
return true, nil
case reflect.Array, reflect.Slice:
// note: the length of i and j may be different
for idx := 0; idx < integer.IntMin(i.Len(), j.Len()); idx++ {
less, err := isLess(i.Index(idx), j.Index(idx))
if err != nil || !less {
return less, err
}
}
return true, nil
default:
return false, fmt.Errorf("unsortable type: %v", i.Kind())
}
}