Initialize scheduler cache with assigned non-terminated pods before scheduling.

cmd/libs/go2idl/informer-gen/generators/factory.go

@@ -127,6 +127,28 @@ func (f *sharedInformerFactory) Start(stopCh <-chan struct{}) {
   }
 }
 
+// WaitForCacheSync waits for all started informers' cache were synced.
+func (f *sharedInformerFactory) WaitForCacheSync(stopCh <-chan struct{}) map[reflect.Type]bool {
+	informers := func()map[reflect.Type]cache.SharedIndexInformer{
+               f.lock.Lock()
+               defer f.lock.Unlock()
+
+               informers := map[reflect.Type]cache.SharedIndexInformer{}
+               for informerType, informer := range f.informers {
+                       if f.startedInformers[informerType] {
+                               informers[informerType] = informer
+                       }
+               }
+               return informers
+       }()
+
+       res := map[reflect.Type]bool{}
+       for informType, informer := range informers {
+               res[informType] = cache.WaitForCacheSync(stopCh, informer.HasSynced)
+       }
+       return res
+}
+
 // InternalInformerFor returns the SharedIndexInformer for obj using an internal
 // client.
 func (f *sharedInformerFactory) InformerFor(obj {{.runtimeObject|raw}}, newFunc {{.interfacesNewInformerFunc|raw}}) {{.cacheSharedIndexInformer|raw}} {
@@ -152,6 +174,7 @@ var sharedInformerFactoryInterface = `
 type SharedInformerFactory interface {
 	{{.informerFactoryInterface|raw}}
 	ForResource(resource {{.schemaGroupVersionResource|raw}}) (GenericInformer, error)
+	WaitForCacheSync(stopCh <-chan struct{}) map[reflect.Type]bool
 
 	{{$gvInterfaces := .gvInterfaces}}
 	{{range $groupName, $group := .groupVersions}}{{$groupName}}() {{index $gvInterfaces $groupName|raw}}

plugin/cmd/kube-scheduler/app/server.go

@@ -94,6 +94,8 @@ func Run(s *options.SchedulerServer) error {
 	stop := make(chan struct{})
 	defer close(stop)
 	informerFactory.Start(stop)
+	// Waiting for all cache to sync before scheduling.
+	informerFactory.WaitForCacheSync(stop)
 
 	run := func(_ <-chan struct{}) {
 		sched.Run()

plugin/pkg/scheduler/factory/factory.go

@@ -380,6 +380,9 @@ func (f *ConfigFactory) CreateFromKeys(predicateKeys, priorityKeys sets.String,
 		Algorithm:           algo,
 		Binder:              &binder{f.client},
 		PodConditionUpdater: &podConditionUpdater{f.client},
+		WaitForCacheSync: func() bool {
+			return cache.WaitForCacheSync(f.StopEverything, f.scheduledPodPopulator.HasSynced)
+		},
 		NextPod: func() *v1.Pod {
 			return f.getNextPod()
 		},

plugin/pkg/scheduler/scheduler.go

@@ -110,6 +110,10 @@ type Config struct {
 	// stale while they sit in a channel.
 	NextPod func() *v1.Pod
 
+	// WaitForCacheSync waits for scheduler cache to populate.
+	// It returns true if it was successful, false if the controller should shutdown.
+	WaitForCacheSync func() bool
+
 	// Error is called if there is an error. It is passed the pod in
 	// question, and the error
 	Error func(*v1.Pod, error)
@@ -140,8 +144,12 @@ func NewFromConfigurator(c Configurator, modifiers ...func(c *Config)) (*Schedul
 	return s, nil
 }
 
-// Run begins watching and scheduling. It starts a goroutine and returns immediately.
+// Run begins watching and scheduling. It waits for cache to be synced, then starts a goroutine and returns immediately.
 func (sched *Scheduler) Run() {
+	if !sched.config.WaitForCacheSync() {
+		return
+	}
+
 	go wait.Until(sched.scheduleOne, 0, sched.config.StopEverything)
 }
 

plugin/pkg/scheduler/scheduler_test.go

@@ -543,6 +543,9 @@ func setupTestSchedulerLongBindingWithRetry(queuedPodStore *clientcache.FIFO, sc
 				bindingChan <- b
 				return nil
 			}},
+			WaitForCacheSync: func() bool {
+				return true
+			},
 			NextPod: func() *v1.Pod {
 				return clientcache.Pop(queuedPodStore).(*v1.Pod)
 			},