Ejemplo n.º 1
0
// ScaleDown tries to scale down the cluster. It returns ScaleDownResult indicating if any node was
// removed and error if such occured.
func ScaleDown(
	nodes []*kube_api.Node,
	unneededNodes map[string]time.Time,
	unneededTime time.Duration,
	pods []*kube_api.Pod,
	gceManager *gce.GceManager,
	client *kube_client.Client,
	predicateChecker *simulator.PredicateChecker) (ScaleDownResult, error) {

	now := time.Now()
	candidates := make([]*kube_api.Node, 0)
	for _, node := range nodes {
		if val, found := unneededNodes[node.Name]; found {

			glog.V(2).Infof("%s was unneeded for %s", node.Name, now.Sub(val).String())

			// Check how long the node was underutilized.
			if !val.Add(unneededTime).Before(now) {
				continue
			}

			// Check mig size.
			instance, err := config.InstanceConfigFromProviderId(node.Spec.ProviderID)
			if err != nil {
				glog.Errorf("Error while parsing providerid of %s: %v", node.Name, err)
				continue
			}
			migConfig, err := gceManager.GetMigForInstance(instance)
			if err != nil {
				glog.Errorf("Error while checking mig config for instance %v: %v", instance, err)
				continue
			}
			size, err := gceManager.GetMigSize(migConfig)
			if err != nil {
				glog.Errorf("Error while checking mig size for instance %v: %v", instance, err)
				continue
			}

			if size <= int64(migConfig.MinSize) {
				glog.V(1).Infof("Skipping %s - mig min size reached", node.Name)
				continue
			}

			candidates = append(candidates, node)
		}
	}
	if len(candidates) == 0 {
		glog.Infof("No candidates for scale down")
		return ScaleDownNoUnneeded, nil
	}

	nodesToRemove, err := simulator.FindNodesToRemove(candidates, nodes, pods, client, predicateChecker, 1, false)
	if err != nil {
		return ScaleDownError, fmt.Errorf("Find node to remove failed: %v", err)
	}
	if len(nodesToRemove) == 0 {
		glog.V(1).Infof("No node to remove")
		return ScaleDownNoNodeDeleted, nil
	}
	nodeToRemove := nodesToRemove[0]
	glog.Infof("Removing %s", nodeToRemove.Name)
	instanceConfig, err := config.InstanceConfigFromProviderId(nodeToRemove.Spec.ProviderID)
	if err != nil {
		return ScaleDownError, fmt.Errorf("Failed to get instance config for %s: %v", nodeToRemove.Name, err)
	}

	err = gceManager.DeleteInstances([]*config.InstanceConfig{instanceConfig})
	if err != nil {
		return ScaleDownError, fmt.Errorf("Failed to delete %v: %v", instanceConfig, err)
	}

	return ScaleDownNodeDeleted, nil
}