Make scheduler not miss deletion events even in the case of a resync.

pkg/client/cache/store.go

@@ -68,6 +68,9 @@ type ExplicitKey string
 // The key uses the format <namespace>/<name> unless <namespace> is empty, then
 // it's just <name>.
 func MetaNamespaceKeyFunc(obj interface{}) (string, error) {
+	if key, ok := obj.(ExplicitKey); ok {
+		return string(key), nil
+	}
 	meta, err := meta.Accessor(obj)
 	if err != nil {
 		return "", fmt.Errorf("object has no meta: %v", err)

plugin/pkg/scheduler/factory/factory.go

@@ -26,6 +26,7 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/client/cache"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/controller/framework"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/fields"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
 	algorithm "github.com/GoogleCloudPlatform/kubernetes/pkg/scheduler"
@@ -51,7 +52,11 @@ type ConfigFactory struct {
 	// a means to list all services
 	ServiceLister *cache.StoreToServiceLister
 
-	modeler scheduler.SystemModeler
+	// Close this to stop all reflectors
+	StopEverything chan struct{}
+
+	scheduledPodPopulator *framework.Controller
+	modeler               scheduler.SystemModeler
 }
 
 // Initializes the factory.
@@ -59,13 +64,40 @@ func NewConfigFactory(client *client.Client) *ConfigFactory {
 	c := &ConfigFactory{
 		Client:             client,
 		PodQueue:           cache.NewFIFO(cache.MetaNamespaceKeyFunc),
-		ScheduledPodLister: &cache.StoreToPodLister{cache.NewStore(cache.MetaNamespaceKeyFunc)},
+		ScheduledPodLister: &cache.StoreToPodLister{},
 		NodeLister:         &cache.StoreToNodeLister{cache.NewStore(cache.MetaNamespaceKeyFunc)},
 		ServiceLister:      &cache.StoreToServiceLister{cache.NewStore(cache.MetaNamespaceKeyFunc)},
+		StopEverything:     make(chan struct{}),
 	}
 	modeler := scheduler.NewSimpleModeler(&cache.StoreToPodLister{c.PodQueue}, c.ScheduledPodLister)
 	c.modeler = modeler
 	c.PodLister = modeler.PodLister()
+
+	// On add/delete to the scheduled pods, remove from the assumed pods.
+	// We construct this here instead of in CreateFromKeys because
+	// ScheduledPodLister is something we provide to plug in functions that
+	// they may need to call.
+	c.ScheduledPodLister.Store, c.scheduledPodPopulator = framework.NewInformer(
+		c.createAssignedPodLW(),
+		&api.Pod{},
+		0,
+		framework.ResourceEventHandlerFuncs{
+			AddFunc: func(obj interface{}) {
+				if pod, ok := obj.(*api.Pod); ok {
+					c.modeler.ForgetPod(pod)
+				}
+			},
+			DeleteFunc: func(obj interface{}) {
+				switch t := obj.(type) {
+				case *api.Pod:
+					c.modeler.ForgetPod(t)
+				case cache.DeletedFinalStateUnknown:
+					c.modeler.ForgetPodByKey(t.Key)
+				}
+			},
+		},
+	)
+
 	return c
 }
 
@@ -109,21 +141,6 @@ func (f *ConfigFactory) CreateFromConfig(policy schedulerapi.Policy) (*scheduler
 	return f.CreateFromKeys(predicateKeys, priorityKeys)
 }
 
-// ReflectorDeletionHook passes all operations through to Store, but calls
-// OnDelete in a goroutine if there is a deletion.
-type ReflectorDeletionHook struct {
-	cache.Store
-	OnDelete func(obj interface{})
-}
-
-func (r ReflectorDeletionHook) Delete(obj interface{}) error {
-	go func() {
-		defer util.HandleCrash()
-		r.OnDelete(obj)
-	}()
-	return r.Store.Delete(obj)
-}
-
 // Creates a scheduler from a set of registered fit predicate keys and priority keys.
 func (f *ConfigFactory) CreateFromKeys(predicateKeys, priorityKeys util.StringSet) (*scheduler.Config, error) {
 	glog.V(2).Infof("creating scheduler with fit predicates '%v' and priority functions '%v", predicateKeys, priorityKeys)
@@ -144,39 +161,25 @@ func (f *ConfigFactory) CreateFromKeys(predicateKeys, priorityKeys util.StringSe
 	}
 
 	// Watch and queue pods that need scheduling.
-	cache.NewReflector(f.createUnassignedPodLW(), &api.Pod{}, f.PodQueue, 0).Run()
+	cache.NewReflector(f.createUnassignedPodLW(), &api.Pod{}, f.PodQueue, 0).RunUntil(f.StopEverything)
 
-	// Pass through all events to the scheduled pod store, but on a deletion,
-	// also remove from the assumed pods.
-	assumedPodDeleter := ReflectorDeletionHook{
-		Store: f.ScheduledPodLister.Store,
-		OnDelete: func(obj interface{}) {
-			if pod, ok := obj.(*api.Pod); ok {
-				f.modeler.LockedAction(func() {
-					f.modeler.ForgetPod(pod)
-				})
-			}
-		},
-	}
-
-	// Watch and cache all running pods. Scheduler needs to find all pods
-	// so it knows where it's safe to place a pod. Cache this locally.
-	cache.NewReflector(f.createAssignedPodLW(), &api.Pod{}, assumedPodDeleter, 0).Run()
+	// Begin populating scheduled pods.
+	f.scheduledPodPopulator.Run(f.StopEverything)
 
 	// Watch minions.
 	// Minions may be listed frequently, so provide a local up-to-date cache.
 	if false {
 		// Disable this code until minions support watches. Note when this code is enabled,
 		// we need to make sure minion ListWatcher has proper FieldSelector.
-		cache.NewReflector(f.createMinionLW(), &api.Node{}, f.NodeLister.Store, 0).Run()
+		cache.NewReflector(f.createMinionLW(), &api.Node{}, f.NodeLister.Store, 10*time.Second).RunUntil(f.StopEverything)
 	} else {
-		cache.NewPoller(f.pollMinions, 10*time.Second, f.NodeLister.Store).Run()
+		cache.NewPoller(f.pollMinions, 10*time.Second, f.NodeLister.Store).RunUntil(f.StopEverything)
 	}
 
 	// Watch and cache all service objects. Scheduler needs to find all pods
 	// created by the same service, so that it can spread them correctly.
 	// Cache this locally.
-	cache.NewReflector(f.createServiceLW(), &api.Service{}, f.ServiceLister.Store, 0).Run()
+	cache.NewReflector(f.createServiceLW(), &api.Service{}, f.ServiceLister.Store, 0).RunUntil(f.StopEverything)
 
 	r := rand.New(rand.NewSource(time.Now().UnixNano()))
 
@@ -200,7 +203,8 @@ func (f *ConfigFactory) CreateFromKeys(predicateKeys, priorityKeys util.StringSe
 			glog.V(2).Infof("About to try and schedule pod %v", pod.Name)
 			return pod
 		},
-		Error: f.makeDefaultErrorFunc(&podBackoff, f.PodQueue),
+		Error:          f.makeDefaultErrorFunc(&podBackoff, f.PodQueue),
+		StopEverything: f.StopEverything,
 	}, nil
 }
 

plugin/pkg/scheduler/modeler.go

@@ -57,8 +57,9 @@ func (a *actionLocker) LockedAction(do func()) {
 
 // FakeModeler implements the SystemModeler interface.
 type FakeModeler struct {
-	AssumePodFunc func(pod *api.Pod)
-	ForgetPodFunc func(pod *api.Pod)
+	AssumePodFunc      func(pod *api.Pod)
+	ForgetPodFunc      func(pod *api.Pod)
+	ForgetPodByKeyFunc func(key string)
 	actionLocker
 }
 
@@ -76,6 +77,13 @@ func (f *FakeModeler) ForgetPod(pod *api.Pod) {
 	}
 }
 
+// ForgetPodByKey calls the function variable if it is not nil.
+func (f *FakeModeler) ForgetPodByKey(key string) {
+	if f.ForgetPodFunc != nil {
+		f.ForgetPodByKeyFunc(key)
+	}
+}
+
 // SimpleModeler implements the SystemModeler interface with a timed pod cache.
 type SimpleModeler struct {
 	queuedPods    ExtendedPodLister
@@ -110,6 +118,10 @@ func (s *SimpleModeler) ForgetPod(pod *api.Pod) {
 	s.assumedPods.Delete(pod)
 }
 
+func (s *SimpleModeler) ForgetPodByKey(key string) {
+	s.assumedPods.Delete(cache.ExplicitKey(key))
+}
+
 // Extract names for readable logging.
 func podNames(pods []api.Pod) []string {
 	out := make([]string, len(pods))

plugin/pkg/scheduler/scheduler.go

@@ -51,6 +51,7 @@ type SystemModeler interface {
 	// show the absence of the given pod if the pod is in the scheduled
 	// pods list!)
 	ForgetPod(pod *api.Pod)
+	ForgetPodByKey(key string)
 
 	// For serializing calls to Assume/ForgetPod: imagine you want to add
 	// a pod iff a bind succeeds, but also remove a pod if it is deleted.
@@ -85,6 +86,9 @@ type Config struct {
 
 	// Recorder is the EventRecorder to use
 	Recorder record.EventRecorder
+
+	// Close this to shut down the scheduler.
+	StopEverything chan struct{}
 }
 
 // New returns a new scheduler.
@@ -98,7 +102,7 @@ func New(c *Config) *Scheduler {
 
 // Run begins watching and scheduling. It starts a goroutine and returns immediately.
 func (s *Scheduler) Run() {
-	go util.Forever(s.scheduleOne, 0)
+	go util.Until(s.scheduleOne, 0, s.config.StopEverything)
 }
 
 func (s *Scheduler) scheduleOne() {