func main() {
glog.Infof("Cluster Autoscaler %s", ClusterAutoscalerVersion)
flag.Var(&nodeGroupsFlag, "nodes", "sets min,max size and other configuration data for a node group in a format accepted by cloud provider."+
"Can be used multiple times. Format: <min>:<max>:<other...>")
flag.Parse()
go func() {
http.Handle("/metrics", prometheus.Handler())
err := http.ListenAndServe(*address, nil)
glog.Fatalf("Failed to start metrics: %v", err)
}()
url, err := url.Parse(*kubernetes)
if err != nil {
glog.Fatalf("Failed to parse Kuberentes url: %v", err)
}
// Configuration
kubeConfig, err := config.GetKubeClientConfig(url)
if err != nil {
glog.Fatalf("Failed to build Kuberentes client configuration: %v", err)
}
kubeClient := kube_client.NewOrDie(kubeConfig)
predicateChecker, err := simulator.NewPredicateChecker(kubeClient)
if err != nil {
glog.Fatalf("Failed to create predicate checker: %v", err)
}
unschedulablePodLister := NewUnschedulablePodLister(kubeClient)
scheduledPodLister := NewScheduledPodLister(kubeClient)
nodeLister := NewNodeLister(kubeClient)
lastScaleUpTime := time.Now()
lastScaleDownFailedTrial := time.Now()
unneededNodes := make(map[string]time.Time)
eventBroadcaster := kube_record.NewBroadcaster()
eventBroadcaster.StartLogging(glog.Infof)
eventBroadcaster.StartRecordingToSink(kubeClient.Events(""))
recorder := eventBroadcaster.NewRecorder(kube_api.EventSource{Component: "cluster-autoscaler"})
var cloudProvider cloudprovider.CloudProvider
if *cloudProviderFlag == "gce" {
// GCE Manager
var gceManager *gce.GceManager
var gceError error
if *cloudConfig != "" {
config, fileErr := os.Open(*cloudConfig)
if fileErr != nil {
glog.Fatalf("Couldn't open cloud provider configuration %s: %#v", *cloudConfig, err)
}
defer config.Close()
gceManager, gceError = gce.CreateGceManager(config)
} else {
gceManager, gceError = gce.CreateGceManager(nil)
}
if gceError != nil {
glog.Fatalf("Failed to create GCE Manager: %v", err)
}
cloudProvider, err = gce.BuildGceCloudProvider(gceManager, nodeGroupsFlag)
if err != nil {
glog.Fatalf("Failed to create GCE cloud provider: %v", err)
}
}
for {
select {
case <-time.After(*scanInterval):
{
loopStart := time.Now()
updateLastTime("main")
nodes, err := nodeLister.List()
if err != nil {
glog.Errorf("Failed to list nodes: %v", err)
continue
}
if len(nodes) == 0 {
glog.Errorf("No nodes in the cluster")
continue
}
if err := CheckGroupsAndNodes(nodes, cloudProvider); err != nil {
glog.Warningf("Cluster is not ready for autoscaling: %v", err)
continue
}
allUnschedulablePods, err := unschedulablePodLister.List()
if err != nil {
glog.Errorf("Failed to list unscheduled pods: %v", err)
continue
}
allScheduled, err := scheduledPodLister.List()
if err != nil {
glog.Errorf("Failed to list scheduled pods: %v", err)
continue
}
// We need to reset all pods that have been marked as unschedulable not after
// the newest node became available for the scheduler.
allNodesAvailableTime := GetAllNodesAvailableTime(nodes)
podsToReset, unschedulablePodsToHelp := SlicePodsByPodScheduledTime(allUnschedulablePods, allNodesAvailableTime)
ResetPodScheduledCondition(kubeClient, podsToReset)
// We need to check whether pods marked as unschedulable are actually unschedulable.
// This should prevent from adding unnecessary nodes. Example of such situation:
// - CA and Scheduler has slightly different configuration
// - Scheduler can't schedule a pod and marks it as unschedulable
// - CA added a node which should help the pod
// - Scheduler doesn't schedule the pod on the new node
// because according to it logic it doesn't fit there
// - CA see the pod is still unschedulable, so it adds another node to help it
//
// With the check enabled the last point won't happen because CA will ignore a pod
// which is supposed to schedule on an existing node.
//
// Without below check cluster might be unnecessary scaled up to the max allowed size
// in the describe situation.
schedulablePodsPresent := false
if *verifyUnschedulablePods {
newUnschedulablePodsToHelp := FilterOutSchedulable(unschedulablePodsToHelp, nodes, allScheduled, predicateChecker)
if len(newUnschedulablePodsToHelp) != len(unschedulablePodsToHelp) {
glog.V(2).Info("Schedulable pods present")
schedulablePodsPresent = true
}
unschedulablePodsToHelp = newUnschedulablePodsToHelp
}
if len(unschedulablePodsToHelp) == 0 {
glog.V(1).Info("No unschedulable pods")
} else {
scaleUpStart := time.Now()
updateLastTime("scaleup")
scaledUp, err := ScaleUp(unschedulablePodsToHelp, nodes, cloudProvider, kubeClient, predicateChecker, recorder)
updateDuration("scaleup", scaleUpStart)
if err != nil {
glog.Errorf("Failed to scale up: %v", err)
continue
} else {
if scaledUp {
lastScaleUpTime = time.Now()
// No scale down in this iteration.
continue
}
}
}
if *scaleDownEnabled {
unneededStart := time.Now()
// In dry run only utilization is updated
calculateUnneededOnly := lastScaleUpTime.Add(*scaleDownDelay).After(time.Now()) ||
lastScaleDownFailedTrial.Add(*scaleDownTrialInterval).After(time.Now()) ||
schedulablePodsPresent
glog.V(4).Infof("Scale down status: unneededOnly=%v lastScaleUpTime=%s "+
"lastScaleDownFailedTrail=%s schedulablePodsPresent=%v", calculateUnneededOnly,
lastScaleUpTime, lastScaleDownFailedTrial, schedulablePodsPresent)
updateLastTime("findUnneeded")
glog.V(4).Infof("Calculating unneded nodes")
unneededNodes = FindUnneededNodes(
nodes,
unneededNodes,
*scaleDownUtilizationThreshold,
allScheduled,
predicateChecker)
updateDuration("findUnneeded", unneededStart)
for key, val := range unneededNodes {
if glog.V(4) {
glog.V(4).Infof("%s is unneeded since %s duration %s", key, val.String(), time.Now().Sub(val).String())
}
}
if !calculateUnneededOnly {
glog.V(4).Infof("Starting scale down")
scaleDownStart := time.Now()
updateLastTime("scaledown")
result, err := ScaleDown(
nodes,
unneededNodes,
*scaleDownUnneededTime,
allScheduled,
cloudProvider, kubeClient, predicateChecker)
updateDuration("scaledown", scaleDownStart)
// TODO: revisit result handling
if err != nil {
glog.Errorf("Failed to scale down: %v", err)
} else {
if result == ScaleDownNodeDeleted {
// Clean the map with unneeded nodes to be super sure that the simulated
// deletions are made in the new context.
unneededNodes = make(map[string]time.Time, len(unneededNodes))
} else {
if result == ScaleDownError || result == ScaleDownNoNodeDeleted {
lastScaleDownFailedTrial = time.Now()
}
}
}
}
}
updateDuration("main", loopStart)
}
}
}
}
// In order to meet interface criteria for LeaderElectionConfig we need to
// take stop channell as an argument. However, since we are committing a suicide
// after loosing mastership we can safely ignore it.
func run(_ <-chan struct{}) {
kubeClient := createKubeClient()
predicateChecker, err := simulator.NewPredicateChecker(kubeClient)
if err != nil {
glog.Fatalf("Failed to create predicate checker: %v", err)
}
unschedulablePodLister := kube_util.NewUnschedulablePodLister(kubeClient, kube_api.NamespaceAll)
scheduledPodLister := kube_util.NewScheduledPodLister(kubeClient)
nodeLister := kube_util.NewNodeLister(kubeClient)
lastScaleUpTime := time.Now()
lastScaleDownFailedTrial := time.Now()
unneededNodes := make(map[string]time.Time)
podLocationHints := make(map[string]string)
usageTracker := simulator.NewUsageTracker()
recorder := createEventRecorder(kubeClient)
var cloudProvider cloudprovider.CloudProvider
if *cloudProviderFlag == "gce" {
// GCE Manager
var gceManager *gce.GceManager
var gceError error
if *cloudConfig != "" {
config, fileErr := os.Open(*cloudConfig)
if fileErr != nil {
glog.Fatalf("Couldn't open cloud provider configuration %s: %#v", *cloudConfig, err)
}
defer config.Close()
gceManager, gceError = gce.CreateGceManager(config)
} else {
gceManager, gceError = gce.CreateGceManager(nil)
}
if gceError != nil {
glog.Fatalf("Failed to create GCE Manager: %v", err)
}
cloudProvider, err = gce.BuildGceCloudProvider(gceManager, nodeGroupsFlag)
if err != nil {
glog.Fatalf("Failed to create GCE cloud provider: %v", err)
}
}
if *cloudProviderFlag == "aws" {
var awsManager *aws.AwsManager
var awsError error
if *cloudConfig != "" {
config, fileErr := os.Open(*cloudConfig)
if fileErr != nil {
glog.Fatalf("Couldn't open cloud provider configuration %s: %#v", *cloudConfig, err)
}
defer config.Close()
awsManager, awsError = aws.CreateAwsManager(config)
} else {
awsManager, awsError = aws.CreateAwsManager(nil)
}
if awsError != nil {
glog.Fatalf("Failed to create AWS Manager: %v", err)
}
cloudProvider, err = aws.BuildAwsCloudProvider(awsManager, nodeGroupsFlag)
if err != nil {
glog.Fatalf("Failed to create AWS cloud provider: %v", err)
}
}
for {
select {
case <-time.After(*scanInterval):
{
loopStart := time.Now()
updateLastTime("main")
nodes, err := nodeLister.List()
if err != nil {
glog.Errorf("Failed to list nodes: %v", err)
continue
}
if len(nodes) == 0 {
glog.Errorf("No nodes in the cluster")
continue
}
if err := CheckGroupsAndNodes(nodes, cloudProvider); err != nil {
glog.Warningf("Cluster is not ready for autoscaling: %v", err)
continue
}
allUnschedulablePods, err := unschedulablePodLister.List()
if err != nil {
glog.Errorf("Failed to list unscheduled pods: %v", err)
continue
}
allScheduled, err := scheduledPodLister.List()
if err != nil {
glog.Errorf("Failed to list scheduled pods: %v", err)
continue
}
// We need to reset all pods that have been marked as unschedulable not after
// the newest node became available for the scheduler.
allNodesAvailableTime := GetAllNodesAvailableTime(nodes)
podsToReset, unschedulablePodsToHelp := SlicePodsByPodScheduledTime(allUnschedulablePods, allNodesAvailableTime)
ResetPodScheduledCondition(kubeClient, podsToReset)
// We need to check whether pods marked as unschedulable are actually unschedulable.
// This should prevent from adding unnecessary nodes. Example of such situation:
// - CA and Scheduler has slightly different configuration
// - Scheduler can't schedule a pod and marks it as unschedulable
// - CA added a node which should help the pod
// - Scheduler doesn't schedule the pod on the new node
// because according to it logic it doesn't fit there
// - CA see the pod is still unschedulable, so it adds another node to help it
//
// With the check enabled the last point won't happen because CA will ignore a pod
// which is supposed to schedule on an existing node.
//
// Without below check cluster might be unnecessary scaled up to the max allowed size
// in the describe situation.
schedulablePodsPresent := false
if *verifyUnschedulablePods {
newUnschedulablePodsToHelp := FilterOutSchedulable(unschedulablePodsToHelp, nodes, allScheduled, predicateChecker)
if len(newUnschedulablePodsToHelp) != len(unschedulablePodsToHelp) {
glog.V(2).Info("Schedulable pods present")
schedulablePodsPresent = true
}
unschedulablePodsToHelp = newUnschedulablePodsToHelp
}
if len(unschedulablePodsToHelp) == 0 {
glog.V(1).Info("No unschedulable pods")
} else if *maxNodesTotal > 0 && len(nodes) >= *maxNodesTotal {
glog.V(1).Info("Max total nodes in cluster reached")
} else {
scaleUpStart := time.Now()
updateLastTime("scaleup")
scaledUp, err := ScaleUp(unschedulablePodsToHelp, nodes, cloudProvider, kubeClient, predicateChecker, recorder,
*maxNodesTotal)
updateDuration("scaleup", scaleUpStart)
if err != nil {
glog.Errorf("Failed to scale up: %v", err)
continue
} else {
if scaledUp {
lastScaleUpTime = time.Now()
// No scale down in this iteration.
continue
}
}
}
if *scaleDownEnabled {
unneededStart := time.Now()
// In dry run only utilization is updated
calculateUnneededOnly := lastScaleUpTime.Add(*scaleDownDelay).After(time.Now()) ||
lastScaleDownFailedTrial.Add(*scaleDownTrialInterval).After(time.Now()) ||
schedulablePodsPresent
glog.V(4).Infof("Scale down status: unneededOnly=%v lastScaleUpTime=%s "+
"lastScaleDownFailedTrail=%s schedulablePodsPresent=%v", calculateUnneededOnly,
lastScaleUpTime, lastScaleDownFailedTrial, schedulablePodsPresent)
updateLastTime("findUnneeded")
glog.V(4).Infof("Calculating unneded nodes")
usageTracker.CleanUp(time.Now().Add(-(*scaleDownUnneededTime)))
unneededNodes, podLocationHints = FindUnneededNodes(
nodes,
unneededNodes,
*scaleDownUtilizationThreshold,
allScheduled,
predicateChecker,
podLocationHints,
usageTracker, time.Now())
updateDuration("findUnneeded", unneededStart)
for key, val := range unneededNodes {
if glog.V(4) {
glog.V(4).Infof("%s is unneeded since %s duration %s", key, val.String(), time.Now().Sub(val).String())
}
}
if !calculateUnneededOnly {
glog.V(4).Infof("Starting scale down")
scaleDownStart := time.Now()
updateLastTime("scaledown")
result, err := ScaleDown(
nodes,
unneededNodes,
*scaleDownUnneededTime,
allScheduled,
cloudProvider,
kubeClient,
predicateChecker,
podLocationHints,
usageTracker)
updateDuration("scaledown", scaleDownStart)
// TODO: revisit result handling
if err != nil {
glog.Errorf("Failed to scale down: %v", err)
} else {
if result == ScaleDownError || result == ScaleDownNoNodeDeleted {
lastScaleDownFailedTrial = time.Now()
}
}
}
}
updateDuration("main", loopStart)
}
}
}
}