adjust the Priority of General and Accurate Estimator of Karmada Scheduler

Signed-off-by: chaosi-zju <[email protected]>

Author: chaosi-zju

pkg/estimator/client/accurate.go

@@ -32,7 +32,7 @@ import (
 
 // RegisterSchedulerEstimator will register a SchedulerEstimator.
 func RegisterSchedulerEstimator(se *SchedulerEstimator) {
-	replicaEstimators["scheduler-estimator"] = se
+	replicaEstimators = append(replicaEstimators, se)
 	unschedulableReplicaEstimators["scheduler-estimator"] = se
 }
 
@@ -68,7 +68,7 @@ func (se *SchedulerEstimator) MaxAvailableReplicas(
 }
 
 func (se *SchedulerEstimator) GetPriority() EstimatorPriority {
-	return High
+	return Accurate
 }
 
 // GetUnschedulableReplicas gets the unschedulable replicas which belong to a specified workload by calling karmada-scheduler-estimator.

pkg/estimator/client/general.go

@@ -32,7 +32,7 @@ import (
 
 // GeneralEstimator is the default replica estimator.
 func init() {
-	replicaEstimators["general-estimator"] = NewGeneralEstimator()
+	replicaEstimators = append(replicaEstimators, NewGeneralEstimator())
 }
 
 // GeneralEstimator is a normal estimator in terms of cluster ResourceSummary.
@@ -54,7 +54,7 @@ func (ge *GeneralEstimator) MaxAvailableReplicas(_ context.Context, clusters []*
 }
 
 func (ge *GeneralEstimator) GetPriority() EstimatorPriority {
-	return Middle
+	return General
 }
 
 func (ge *GeneralEstimator) maxAvailableReplicas(cluster *clusterv1alpha1.Cluster, replicaRequirements *workv1alpha2.ReplicaRequirements) int32 {

pkg/estimator/client/interface.go

@@ -30,7 +30,7 @@ import (
 const UnauthenticReplica = -1
 
 var (
-	replicaEstimators              = map[string]ReplicaEstimator{}
+	replicaEstimators              []ReplicaEstimator
 	unschedulableReplicaEstimators = map[string]UnschedulableReplicaEstimator{}
 )
 
@@ -46,7 +46,7 @@ type UnschedulableReplicaEstimator interface {
 }
 
 // GetReplicaEstimators returns all replica estimators.
-func GetReplicaEstimators() map[string]ReplicaEstimator {
+func GetReplicaEstimators() []ReplicaEstimator {
 	return replicaEstimators
 }
 
@@ -59,11 +59,10 @@ func GetUnschedulableReplicaEstimators() map[string]UnschedulableReplicaEstimato
 // 1. Higher-priority estimator can directly override the result given by lower-priority estimator
 // 2. Lower replicas estimated will be chosen if the priority of estimator are same
 // 3. Lower-priority estimator would be ignored if the result was already given by higher-priority estimator
-type EstimatorPriority int
+type EstimatorPriority int32
 
 const (
-	Undefined EstimatorPriority = iota
-	Low
-	Middle
-	High
+	Rough    EstimatorPriority = 100
+	General  EstimatorPriority = 200
+	Accurate EstimatorPriority = 300
 )

pkg/scheduler/core/util.go

@@ -20,6 +20,7 @@ import (
 	"context"
 	"fmt"
 	"math"
+	"sort"
 
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/klog/v2"
@@ -53,22 +54,13 @@ func getDefaultWeightPreference(clusters []*clusterv1alpha1.Cluster) *policyv1al
 
 func calAvailableReplicas(clusters []*clusterv1alpha1.Cluster, spec *workv1alpha2.ResourceBindingSpec) []workv1alpha2.TargetCluster {
 	availableTargetClusters := make([]workv1alpha2.TargetCluster, len(clusters))
-	// availableResultPriority indicates which priority Estimator gives the scheduling result for each cluster, respectively
-	// 1. Higher-priority estimator can directly override the result given by lower-priority estimator
-	// 2. Lower replicas estimated will be chosen if the priority of estimator are same
-	// 3. Lower-priority estimator would be ignored if the result was already given by higher-priority estimator
-	availableResultPriority := make([]estimatorclient.EstimatorPriority, len(clusters))
 
 	// Set the boundary.
 	for i := range availableTargetClusters {
 		availableTargetClusters[i].Name = clusters[i].Name
 		availableTargetClusters[i].Replicas = math.MaxInt32
 	}
 
-	for i := range availableResultPriority {
-		availableResultPriority[i] = estimatorclient.Undefined
-	}
-
 	// For non-workload, like ServiceAccount, ConfigMap, Secret and etc, it's unnecessary to calculate available replicas in member clusters.
 	// See issue: https://github.com/karmada-io/karmada/issues/3743.
 	if spec.Replicas == 0 {
@@ -79,30 +71,29 @@ func calAvailableReplicas(clusters []*clusterv1alpha1.Cluster, spec *workv1alpha
 
 	// Get the minimum value of MaxAvailableReplicas in terms of all estimators.
 	estimators := estimatorclient.GetReplicaEstimators()
+	sort.Slice(estimators, func(i, j int) bool {
+		return estimators[i].GetPriority() > estimators[j].GetPriority()
+	})
+
+	priorityOfAvailableEstimator := estimatorclient.EstimatorPriority(math.MinInt32)
 	ctx := context.WithValue(context.TODO(), util.ContextKeyObject,
 		fmt.Sprintf("kind=%s, name=%s/%s", spec.Resource.Kind, spec.Resource.Namespace, spec.Resource.Name))
 	for _, estimator := range estimators {
+		if estimator.GetPriority() < priorityOfAvailableEstimator {
+			break
+		}
 		res, err := estimator.MaxAvailableReplicas(ctx, clusters, spec.ReplicaRequirements)
 		if err != nil {
 			klog.Errorf("Max cluster available replicas error: %v", err)
 			continue
 		}
+		priorityOfAvailableEstimator = estimator.GetPriority()
 		for i := range res {
-			if res[i].Name != availableTargetClusters[i].Name {
-				continue
-			}
 			if res[i].Replicas == estimatorclient.UnauthenticReplica {
 				continue
 			}
-			// means there are already replicas calculated by higher-priority estimator
-			if estimator.GetPriority() < availableResultPriority[i] {
-				continue
-			}
-			// override if current estimator has higher priority and take lower replicas is estimator priority are same
-			if (estimator.GetPriority() == availableResultPriority[i] && res[i].Replicas < availableTargetClusters[i].Replicas) ||
-				estimator.GetPriority() > availableResultPriority[i] {
+			if availableTargetClusters[i].Name == res[i].Name && availableTargetClusters[i].Replicas > res[i].Replicas {
 				availableTargetClusters[i].Replicas = res[i].Replicas
-				availableResultPriority[i] = estimator.GetPriority()
 			}
 		}
 	}