Merge pull request #122435 from aleksandra-malinowska/scheduler-first-fit-3

Scheduler first fit

pkg/scheduler/extender.go

@@ -383,6 +383,11 @@ func (h *HTTPExtender) IsBinder() bool {
 	return h.bindVerb != ""
 }
 
+// IsPrioritizer returns whether this extender is configured for the Prioritize method.
+func (h *HTTPExtender) IsPrioritizer() bool {
+	return h.prioritizeVerb != ""
+}
+
 // Helper function to send messages to the extender
 func (h *HTTPExtender) send(action string, args interface{}, result interface{}) error {
 	out, err := json.Marshal(args)

pkg/scheduler/extender_test.go

@@ -93,6 +93,7 @@ func TestSchedulerWithExtenders(t *testing.T) {
 			registerPlugins: []tf.RegisterPluginFunc{
 				tf.RegisterFilterPlugin("TrueFilter", tf.NewTrueFilterPlugin),
 				tf.RegisterQueueSortPlugin(queuesort.Name, queuesort.New),
+				tf.RegisterScorePlugin("EqualPrioritizerPlugin", tf.NewEqualPrioritizerPlugin(), 20),
 				tf.RegisterBindPlugin(defaultbinder.Name, defaultbinder.New),
 			},
 			extenders: []tf.FakeExtender{
@@ -245,6 +246,7 @@ func TestSchedulerWithExtenders(t *testing.T) {
 			// because of the errors from errorPredicateExtender.
 			registerPlugins: []tf.RegisterPluginFunc{
 				tf.RegisterFilterPlugin("TrueFilter", tf.NewTrueFilterPlugin),
+				tf.RegisterScorePlugin("EqualPrioritizerPlugin", tf.NewEqualPrioritizerPlugin(), 20),
 				tf.RegisterQueueSortPlugin(queuesort.Name, queuesort.New),
 				tf.RegisterBindPlugin(defaultbinder.Name, defaultbinder.New),
 			},
@@ -268,6 +270,30 @@ func TestSchedulerWithExtenders(t *testing.T) {
 			},
 			name: "test 9",
 		},
+		{
+			registerPlugins: []tf.RegisterPluginFunc{
+				tf.RegisterFilterPlugin("TrueFilter", tf.NewTrueFilterPlugin),
+				tf.RegisterQueueSortPlugin(queuesort.Name, queuesort.New),
+				tf.RegisterBindPlugin(defaultbinder.Name, defaultbinder.New),
+			},
+			extenders: []tf.FakeExtender{
+				{
+					ExtenderName: "FakeExtender1",
+					Predicates:   []tf.FitPredicate{tf.TruePredicateExtender},
+				},
+				{
+					ExtenderName: "FakeExtender2",
+					Predicates:   []tf.FitPredicate{tf.Node1PredicateExtender},
+				},
+			},
+			nodes: []string{"node1", "node2"},
+			expectedResult: ScheduleResult{
+				SuggestedHost:  "node1",
+				EvaluatedNodes: 1,
+				FeasibleNodes:  1,
+			},
+			name: "test 10",
+		},
 	}
 
 	for _, test := range tests {

pkg/scheduler/framework/extender.go

@@ -50,6 +50,9 @@ type Extender interface {
 	// this pod is managed by this extender.
 	IsInterested(pod *v1.Pod) bool
 
+	// IsPrioritizer returns whether this extender is configured for the Prioritize method.
+	IsPrioritizer() bool
+
 	// ProcessPreemption returns nodes with their victim pods processed by extender based on
 	// given:
 	//   1. Pod to schedule

pkg/scheduler/schedule_one.go

@@ -422,7 +422,7 @@ func (sched *Scheduler) schedulePod(ctx context.Context, fwk framework.Framework
 		}, nil
 	}
 
-	priorityList, err := prioritizeNodes(ctx, sched.Extenders, fwk, state, pod, feasibleNodes)
+	priorityList, err := sched.prioritizeNodes(ctx, fwk, state, pod, feasibleNodes)
 	if err != nil {
 		return result, err
 	}
@@ -544,6 +544,19 @@ func (sched *Scheduler) evaluateNominatedNode(ctx context.Context, pod *v1.Pod,
 	return feasibleNodes, nil
 }
 
+// hasScoring checks if scoring nodes is configured.
+func (sched *Scheduler) hasScoring(fwk framework.Framework) bool {
+	if fwk.HasScorePlugins() {
+		return true
+	}
+	for _, extender := range sched.Extenders {
+		if extender.IsPrioritizer() {
+			return true
+		}
+	}
+	return false
+}
+
 // findNodesThatPassFilters finds the nodes that fit the filter plugins.
 func (sched *Scheduler) findNodesThatPassFilters(
 	ctx context.Context,
@@ -554,6 +567,9 @@ func (sched *Scheduler) findNodesThatPassFilters(
 	nodes []*framework.NodeInfo) ([]*framework.NodeInfo, error) {
 	numAllNodes := len(nodes)
 	numNodesToFind := sched.numFeasibleNodesToFind(fwk.PercentageOfNodesToScore(), int32(numAllNodes))
+	if !sched.hasScoring(fwk) {
+		numNodesToFind = 1
+	}
 
 	// Create feasible list with enough space to avoid growing it
 	// and allow assigning.
@@ -705,9 +721,8 @@ func findNodesThatPassExtenders(ctx context.Context, extenders []framework.Exten
 // The scores from each plugin are added together to make the score for that node, then
 // any extenders are run as well.
 // All scores are finally combined (added) to get the total weighted scores of all nodes
-func prioritizeNodes(
+func (sched *Scheduler) prioritizeNodes(
 	ctx context.Context,
-	extenders []framework.Extender,
 	fwk framework.Framework,
 	state *framework.CycleState,
 	pod *v1.Pod,
@@ -716,7 +731,7 @@ func prioritizeNodes(
 	logger := klog.FromContext(ctx)
 	// If no priority configs are provided, then all nodes will have a score of one.
 	// This is required to generate the priority list in the required format
-	if len(extenders) == 0 && !fwk.HasScorePlugins() {
+	if !sched.hasScoring(fwk) {
 		result := make([]framework.NodePluginScores, 0, len(nodes))
 		for i := range nodes {
 			result = append(result, framework.NodePluginScores{
@@ -749,14 +764,17 @@ func prioritizeNodes(
 		}
 	}
 
-	if len(extenders) != 0 && nodes != nil {
+	if len(sched.Extenders) != 0 && nodes != nil {
 		// allNodeExtendersScores has all extenders scores for all nodes.
 		// It is keyed with node name.
 		allNodeExtendersScores := make(map[string]*framework.NodePluginScores, len(nodes))
 		var mu sync.Mutex
 		var wg sync.WaitGroup
-		for i := range extenders {
-			if !extenders[i].IsInterested(pod) {
+		for i := range sched.Extenders {
+			if !sched.Extenders[i].IsInterested(pod) {
+				continue
+			}
+			if !sched.Extenders[i].IsPrioritizer() {
 				continue
 			}
 			wg.Add(1)
@@ -766,10 +784,10 @@ func prioritizeNodes(
 					metrics.Goroutines.WithLabelValues(metrics.PrioritizingExtender).Dec()
 					wg.Done()
 				}()
-				prioritizedList, weight, err := extenders[extIndex].Prioritize(pod, nodes)
+				prioritizedList, weight, err := sched.Extenders[extIndex].Prioritize(pod, nodes)
 				if err != nil {
 					// Prioritization errors from extender can be ignored, let k8s/other extenders determine the priorities
-					logger.V(5).Info("Failed to run extender's priority function. No score given by this extender.", "error", err, "pod", klog.KObj(pod), "extender", extenders[extIndex].Name())
+					logger.V(5).Info("Failed to run extender's priority function. No score given by this extender.", "error", err, "pod", klog.KObj(pod), "extender", sched.Extenders[extIndex].Name())
 					return
 				}
 				mu.Lock()
@@ -778,7 +796,7 @@ func prioritizeNodes(
 					nodename := (*prioritizedList)[i].Host
 					score := (*prioritizedList)[i].Score
 					if loggerVTen.Enabled() {
-						loggerVTen.Info("Extender scored node for pod", "pod", klog.KObj(pod), "extender", extenders[extIndex].Name(), "node", nodename, "score", score)
+						loggerVTen.Info("Extender scored node for pod", "pod", klog.KObj(pod), "extender", sched.Extenders[extIndex].Name(), "node", nodename, "score", score)
 					}
 
 					// MaxExtenderPriority may diverge from the max priority used in the scheduler and defined by MaxNodeScore,
@@ -788,11 +806,11 @@ func prioritizeNodes(
 					if allNodeExtendersScores[nodename] == nil {
 						allNodeExtendersScores[nodename] = &framework.NodePluginScores{
 							Name:   nodename,
-							Scores: make([]framework.PluginScore, 0, len(extenders)),
+							Scores: make([]framework.PluginScore, 0, len(sched.Extenders)),
 						}
 					}
 					allNodeExtendersScores[nodename].Scores = append(allNodeExtendersScores[nodename].Scores, framework.PluginScore{
-						Name:  extenders[extIndex].Name(),
+						Name:  sched.Extenders[extIndex].Name(),
 						Score: finalscore,
 					})
 					allNodeExtendersScores[nodename].TotalScore += finalscore

pkg/scheduler/schedule_one_test.go

@@ -91,6 +91,7 @@ type fakeExtender struct {
 	interestedPodName string
 	ignorable         bool
 	gotBind           bool
+	isPrioritizer     bool
 }
 
 func (f *fakeExtender) Name() string {
@@ -140,6 +141,10 @@ func (f *fakeExtender) IsInterested(pod *v1.Pod) bool {
 	return pod != nil && pod.Name == f.interestedPodName
 }
 
+func (f *fakeExtender) IsPrioritizer() bool {
+	return f.isPrioritizer
+}
+
 type falseMapPlugin struct{}
 
 func newFalseMapPlugin() frameworkruntime.PluginFactory {
@@ -1809,6 +1814,7 @@ func TestSchedulerSchedulePod(t *testing.T) {
 			registerPlugins: []tf.RegisterPluginFunc{
 				tf.RegisterQueueSortPlugin(queuesort.Name, queuesort.New),
 				tf.RegisterFilterPlugin("TrueFilter", tf.NewTrueFilterPlugin),
+				tf.RegisterScorePlugin("EqualPrioritizerPlugin", tf.NewEqualPrioritizerPlugin(), 20),
 				tf.RegisterBindPlugin(defaultbinder.Name, defaultbinder.New),
 			},
 			nodes:     []string{"node1", "node2"},
@@ -1926,6 +1932,7 @@ func TestSchedulerSchedulePod(t *testing.T) {
 				tf.RegisterQueueSortPlugin(queuesort.Name, queuesort.New),
 				tf.RegisterPreFilterPlugin(volumebinding.Name, frameworkruntime.FactoryAdapter(fts, volumebinding.New)),
 				tf.RegisterFilterPlugin("TrueFilter", tf.NewTrueFilterPlugin),
+				tf.RegisterScorePlugin("EqualPrioritizerPlugin", tf.NewEqualPrioritizerPlugin(), 20),
 				tf.RegisterBindPlugin(defaultbinder.Name, defaultbinder.New),
 			},
 			nodes: []string{"node1", "node2"},
@@ -2039,6 +2046,7 @@ func TestSchedulerSchedulePod(t *testing.T) {
 					"PreFilter",
 					"Filter",
 				),
+				tf.RegisterScorePlugin("EqualPrioritizerPlugin", tf.NewEqualPrioritizerPlugin(), 20),
 				tf.RegisterBindPlugin(defaultbinder.Name, defaultbinder.New),
 			},
 			nodes: []string{"node1", "node2", "node3"},
@@ -2312,6 +2320,7 @@ func TestSchedulerSchedulePod(t *testing.T) {
 						},
 					}, nil
 				}, "PreFilter", "Filter"),
+				tf.RegisterScorePlugin("EqualPrioritizerPlugin", tf.NewEqualPrioritizerPlugin(), 20),
 				tf.RegisterBindPlugin(defaultbinder.Name, defaultbinder.New),
 			},
 			nodes:              []string{"node1", "node2", "node3"},
@@ -2334,6 +2343,33 @@ func TestSchedulerSchedulePod(t *testing.T) {
 			pod:       st.MakePod().Name("ignore").UID("ignore").Obj(),
 			wantNodes: sets.New("node1", "node2"),
 		},
+		{
+			name: "test without score plugin no extra nodes are evaluated",
+			registerPlugins: []tf.RegisterPluginFunc{
+				tf.RegisterQueueSortPlugin(queuesort.Name, queuesort.New),
+				tf.RegisterFilterPlugin("TrueFilter", tf.NewTrueFilterPlugin),
+				tf.RegisterBindPlugin(defaultbinder.Name, defaultbinder.New),
+			},
+			nodes:              []string{"node1", "node2", "node3"},
+			pod:                st.MakePod().Name("pod1").UID("pod1").Obj(),
+			wantNodes:          sets.New("node1", "node2", "node3"),
+			wantEvaluatedNodes: ptr.To[int32](1),
+		},
+		{
+			name: "test no score plugin, prefilter plugin returning 2 nodes, only 1 node is evaluated",
+			registerPlugins: []tf.RegisterPluginFunc{
+				tf.RegisterQueueSortPlugin(queuesort.Name, queuesort.New),
+				tf.RegisterPreFilterPlugin(
+					"FakePreFilter",
+					tf.NewFakePreFilterPlugin("FakePreFilter", &framework.PreFilterResult{NodeNames: sets.New("node1", "node2")}, nil),
+				),
+				tf.RegisterBindPlugin(defaultbinder.Name, defaultbinder.New),
+			},
+			nodes:              []string{"node1", "node2", "node3"},
+			pod:                st.MakePod().Name("test-prefilter").UID("test-prefilter").Obj(),
+			wantNodes:          sets.New("node1", "node2"),
+			wantEvaluatedNodes: ptr.To[int32](1),
+		},
 	}
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
@@ -2707,7 +2743,7 @@ func TestZeroRequest(t *testing.T) {
 				t.Fatalf("error filtering nodes: %+v", err)
 			}
 			fwk.RunPreScorePlugins(ctx, state, test.pod, tf.BuildNodeInfos(test.nodes))
-			list, err := prioritizeNodes(ctx, nil, fwk, state, test.pod, tf.BuildNodeInfos(test.nodes))
+			list, err := sched.prioritizeNodes(ctx, fwk, state, test.pod, tf.BuildNodeInfos(test.nodes))
 			if err != nil {
 				t.Errorf("unexpected error: %v", err)
 			}
@@ -3103,7 +3139,10 @@ func Test_prioritizeNodes(t *testing.T) {
 			for ii := range test.extenders {
 				extenders = append(extenders, &test.extenders[ii])
 			}
-			nodesscores, err := prioritizeNodes(ctx, extenders, fwk, state, test.pod, tf.BuildNodeInfos(test.nodes))
+			sched := &Scheduler{
+				Extenders: extenders,
+			}
+			nodesscores, err := sched.prioritizeNodes(ctx, fwk, state, test.pod, tf.BuildNodeInfos(test.nodes))
 			if err != nil {
 				t.Errorf("unexpected error: %v", err)
 			}
@@ -3206,6 +3245,7 @@ func TestFairEvaluationForNodes(t *testing.T) {
 		[]tf.RegisterPluginFunc{
 			tf.RegisterQueueSortPlugin(queuesort.Name, queuesort.New),
 			tf.RegisterFilterPlugin("TrueFilter", tf.NewTrueFilterPlugin),
+			tf.RegisterScorePlugin("EqualPrioritizerPlugin", tf.NewEqualPrioritizerPlugin(), 20),
 			tf.RegisterBindPlugin(defaultbinder.Name, defaultbinder.New),
 		},
 		"",
@@ -3284,6 +3324,7 @@ func TestPreferNominatedNodeFilterCallCounts(t *testing.T) {
 			registerPlugins := []tf.RegisterPluginFunc{
 				tf.RegisterQueueSortPlugin(queuesort.Name, queuesort.New),
 				registerFakeFilterFunc,
+				tf.RegisterScorePlugin("EqualPrioritizerPlugin", tf.NewEqualPrioritizerPlugin(), 20),
 				tf.RegisterBindPlugin(defaultbinder.Name, defaultbinder.New),
 			}
 			fwk, err := tf.NewFramework(

pkg/scheduler/testing/framework/fake_extender.go

@@ -137,6 +137,30 @@ func (pl *node2PrioritizerPlugin) ScoreExtensions() framework.ScoreExtensions {
 	return nil
 }
 
+type equalPrioritizerPlugin struct{}
+
+// NewEqualPrioritizerPlugin returns a factory function to build equalPrioritizerPlugin.
+func NewEqualPrioritizerPlugin() frameworkruntime.PluginFactory {
+	return func(_ context.Context, _ runtime.Object, _ framework.Handle) (framework.Plugin, error) {
+		return &equalPrioritizerPlugin{}, nil
+	}
+}
+
+// Name returns the name of the plugin.
+func (pl *equalPrioritizerPlugin) Name() string {
+	return "EqualPrioritizerPlugin"
+}
+
+// Score returns score 1 for each node.
+func (pl *equalPrioritizerPlugin) Score(_ context.Context, _ *framework.CycleState, _ *v1.Pod, _ string) (int64, *framework.Status) {
+	return int64(1), nil
+}
+
+// ScoreExtensions returns nil.
+func (pl *equalPrioritizerPlugin) ScoreExtensions() framework.ScoreExtensions {
+	return nil
+}
+
 // FakeExtender is a data struct which implements the Extender interface.
 type FakeExtender struct {
 	// ExtenderName indicates this fake extender's name.
@@ -380,6 +404,11 @@ func (f *FakeExtender) IsBinder() bool {
 	return true
 }
 
+// IsPrioritizer returns true if there are any prioritizers.
+func (f *FakeExtender) IsPrioritizer() bool {
+	return len(f.Prioritizers) > 0
+}
+
 // IsInterested returns a bool indicating whether this extender is interested in this Pod.
 func (f *FakeExtender) IsInterested(pod *v1.Pod) bool {
 	return !f.UnInterested