daemon: add custom node indexer

pkg/controller/daemon/daemon_controller.go

@@ -113,6 +113,8 @@ type DaemonSetsController struct {
 	historyStoreSynced cache.InformerSynced
 	// podLister get list/get pods from the shared informers's store
 	podLister corelisters.PodLister
+	// podNodeIndex indexes pods by their nodeName
+	podNodeIndex cache.Indexer
 	// podStoreSynced returns true if the pod store has been synced at least once.
 	// Added as a member to the struct to allow injection for testing.
 	podStoreSynced cache.InformerSynced
@@ -191,6 +193,12 @@ func NewDaemonSetsController(daemonSetInformer appsinformers.DaemonSetInformer,
 		DeleteFunc: dsc.deletePod,
 	})
 	dsc.podLister = podInformer.Lister()
+
+	// This custom indexer will index pods based on their NodeName which will decrease the amount of pods we need to get in simulate() call.
+	podInformer.Informer().GetIndexer().AddIndexers(cache.Indexers{
+		"nodeName": indexByPodNodeName,
+	})
+	dsc.podNodeIndex = podInformer.Informer().GetIndexer()
 	dsc.podStoreSynced = podInformer.Informer().HasSynced
 
 	nodeInformer.Informer().AddEventHandler(cache.ResourceEventHandlerFuncs{
@@ -207,6 +215,18 @@ func NewDaemonSetsController(daemonSetInformer appsinformers.DaemonSetInformer,
 	return dsc, nil
 }
 
+func indexByPodNodeName(obj interface{}) ([]string, error) {
+	pod, ok := obj.(*v1.Pod)
+	if !ok {
+		return []string{}, nil
+	}
+	// We are only interested in active pods with nodeName set
+	if len(pod.Spec.NodeName) == 0 || pod.Status.Phase == v1.PodSucceeded || pod.Status.Phase == v1.PodFailed {
+		return []string{}, nil
+	}
+	return []string{pod.Spec.NodeName}, nil
+}
+
 func (dsc *DaemonSetsController) deleteDaemonset(obj interface{}) {
 	ds, ok := obj.(*apps.DaemonSet)
 	if !ok {
@@ -1272,31 +1292,27 @@ func (dsc *DaemonSetsController) simulate(newPod *v1.Pod, node *v1.Node, ds *app
 		})
 	}
 
-	pods := []*v1.Pod{}
-
-	podList, err := dsc.podLister.List(labels.Everything())
+	objects, err := dsc.podNodeIndex.ByIndex("nodeName", node.Name)
 	if err != nil {
 		return nil, nil, err
 	}
-	for _, pod := range podList {
-		if pod.Spec.NodeName != node.Name {
-			continue
-		}
-		if pod.Status.Phase == v1.PodSucceeded || pod.Status.Phase == v1.PodFailed {
-			continue
-		}
-		// ignore pods that belong to the daemonset when taking into account whether
-		// a daemonset should bind to a node.
+
+	nodeInfo := schedulercache.NewNodeInfo()
+	nodeInfo.SetNode(node)
+
+	for _, obj := range objects {
+		// Ignore pods that belong to the daemonset when taking into account whether a daemonset should bind to a node.
 		// TODO: replace this with metav1.IsControlledBy() in 1.12
+		pod, ok := obj.(*v1.Pod)
+		if !ok {
+			continue
+		}
 		if isControlledByDaemonSet(pod, ds.GetUID()) {
 			continue
 		}
-		pods = append(pods, pod)
+		nodeInfo.AddPod(pod)
 	}
 
-	nodeInfo := schedulercache.NewNodeInfo(pods...)
-	nodeInfo.SetNode(node)
-
 	_, reasons, err := Predicates(newPod, nodeInfo)
 	return reasons, nodeInfo, err
 }

pkg/controller/daemon/daemon_controller_test.go

@@ -1953,6 +1953,7 @@ func TestNodeShouldRunDaemonPod(t *testing.T) {
 			for _, p := range c.podsOnNode {
 				manager.podStore.Add(p)
 				p.Spec.NodeName = "test-node"
+				manager.podNodeIndex.Add(p)
 			}
 			c.ds.Spec.UpdateStrategy = *strategy
 			wantToRun, shouldSchedule, shouldContinueRunning, err := manager.nodeShouldRunDaemonPod(node, c.ds)