Eclass Task 1: clean up old equiv class code

Co-authored-by: Harry Zhang <resouer@gmail.com>
Co-authored-by: Wang Qingcan <wangqingcan@baidu.com>

cmd/kube-scheduler/app/server.go

@@ -187,7 +187,6 @@ func Run(cc schedulerserverconfig.CompletedConfig, stopCh <-chan struct{}) error
 		stopCh,
 		scheduler.WithName(cc.ComponentConfig.SchedulerName),
 		scheduler.WithHardPodAffinitySymmetricWeight(cc.ComponentConfig.HardPodAffinitySymmetricWeight),
-		scheduler.WithEquivalenceClassCacheEnabled(cc.ComponentConfig.EnableContentionProfiling),
 		scheduler.WithPreemptionDisabled(cc.ComponentConfig.DisablePreemption),
 		scheduler.WithPercentageOfNodesToScore(cc.ComponentConfig.PercentageOfNodesToScore),
 		scheduler.WithBindTimeoutSeconds(*cc.ComponentConfig.BindTimeoutSeconds))
@@ -356,7 +355,6 @@ func NewSchedulerConfig(s schedulerserverconfig.CompletedConfig) (*factory.Confi
 		PdbInformer:                    s.InformerFactory.Policy().V1beta1().PodDisruptionBudgets(),
 		StorageClassInformer:           storageClassInformer,
 		HardPodAffinitySymmetricWeight: s.ComponentConfig.HardPodAffinitySymmetricWeight,
-		EnableEquivalenceClassCache:    utilfeature.DefaultFeatureGate.Enabled(features.EnableEquivalenceClassCache),
 		DisablePreemption:              s.ComponentConfig.DisablePreemption,
 		PercentageOfNodesToScore:       s.ComponentConfig.PercentageOfNodesToScore,
 		BindTimeoutSeconds:             *s.ComponentConfig.BindTimeoutSeconds,

pkg/features/kube_features.go

@@ -124,12 +124,6 @@ const (
 	// Add priority to pods. Priority affects scheduling and preemption of pods.
 	PodPriority utilfeature.Feature = "PodPriority"
 
-	// owner: @resouer
-	// alpha: v1.8
-	//
-	// Enable equivalence class cache for scheduler.
-	EnableEquivalenceClassCache utilfeature.Feature = "EnableEquivalenceClassCache"
-
 	// owner: @k82cn
 	// beta: v1.12
 	//
@@ -418,7 +412,6 @@ var defaultKubernetesFeatureGates = map[utilfeature.Feature]utilfeature.FeatureS
 	DebugContainers:                             {Default: false, PreRelease: utilfeature.Alpha},
 	PodShareProcessNamespace:                    {Default: true, PreRelease: utilfeature.Beta},
 	PodPriority:                                 {Default: true, PreRelease: utilfeature.Beta},
-	EnableEquivalenceClassCache:                 {Default: false, PreRelease: utilfeature.Alpha},
 	TaintNodesByCondition:                       {Default: true, PreRelease: utilfeature.Beta},
 	MountPropagation:                            {Default: true, PreRelease: utilfeature.GA},
 	QOSReserved:                                 {Default: false, PreRelease: utilfeature.Alpha},

pkg/scheduler/algorithmprovider/defaults/compatibility_test.go

@@ -36,8 +36,6 @@ import (
 	"k8s.io/kubernetes/pkg/scheduler/factory"
 )
 
-const enableEquivalenceCache = true
-
 func TestCompatibility_v1_Scheduler(t *testing.T) {
 	// Add serialized versions of scheduler config that exercise available options to ensure compatibility between releases
 	schedulerFiles := map[string]struct {
@@ -987,7 +985,6 @@ func TestCompatibility_v1_Scheduler(t *testing.T) {
 			PdbInformer:                    informerFactory.Policy().V1beta1().PodDisruptionBudgets(),
 			StorageClassInformer:           informerFactory.Storage().V1().StorageClasses(),
 			HardPodAffinitySymmetricWeight: v1.DefaultHardPodAffinitySymmetricWeight,
-			EnableEquivalenceClassCache:    enableEquivalenceCache,
 			DisablePreemption:              false,
 			PercentageOfNodesToScore:       schedulerapi.DefaultPercentageOfNodesToScore,
 		}).CreateFromConfig(policy); err != nil {

pkg/scheduler/algorithmprovider/defaults/defaults.go

@@ -49,13 +49,6 @@ func init() {
 	registerAlgorithmProvider(defaultPredicates(), defaultPriorities())
 
 	// IMPORTANT NOTES for predicate developers:
-	// We are using cached predicate result for pods belonging to the same equivalence class.
-	// So when implementing a new predicate, you are expected to check whether the result
-	// of your predicate function can be affected by related API object change (ADD/DELETE/UPDATE).
-	// If yes, you are expected to invalidate the cached predicate result for related API object change.
-	// For example:
-	// https://github.com/kubernetes/kubernetes/blob/36a218e/plugin/pkg/scheduler/factory/factory.go#L422
-
 	// Registers predicates and priorities that are not enabled by default, but user can pick when creating their
 	// own set of priorities/predicates.