karmada/pkg/scheduler/core/generic_shceduler.go

141 lines
4.5 KiB
Go

package core
import (
"context"
"fmt"
"k8s.io/klog/v2"
clusterapi "github.com/karmada-io/karmada/pkg/apis/cluster/v1alpha1"
"github.com/karmada-io/karmada/pkg/apis/policy/v1alpha1"
lister "github.com/karmada-io/karmada/pkg/generated/listers/propagationstrategy/v1alpha1"
"github.com/karmada-io/karmada/pkg/scheduler/cache"
"github.com/karmada-io/karmada/pkg/scheduler/framework"
"github.com/karmada-io/karmada/pkg/scheduler/framework/runtime"
)
// ScheduleAlgorithm is the interface that should be implemented to schedule a resource to the target clusters.
type ScheduleAlgorithm interface {
Schedule(context.Context, *v1alpha1.PropagationBinding) (scheduleResult ScheduleResult, err error)
}
// ScheduleResult includes the clusters selected.
type ScheduleResult struct {
SuggestedClusters []string
}
type genericScheduler struct {
schedulerCache cache.Cache
// TODO: move it into schedulerCache
policyLister lister.PropagationPolicyLister
scheduleFramework framework.Framework
}
// NewGenericScheduler creates a genericScheduler object.
func NewGenericScheduler(
schedCache cache.Cache,
policyLister lister.PropagationPolicyLister,
plugins []string,
) ScheduleAlgorithm {
return &genericScheduler{
schedulerCache: schedCache,
policyLister: policyLister,
scheduleFramework: runtime.NewFramework(plugins),
}
}
func (g *genericScheduler) Schedule(ctx context.Context, binding *v1alpha1.PropagationBinding) (result ScheduleResult, err error) {
klog.V(4).Infof("Scheduling %s/%s", binding.Namespace, binding.Name)
clusterInfoSnapshot := g.schedulerCache.Snapshot()
if clusterInfoSnapshot.NumOfClusters() == 0 {
return result, fmt.Errorf("no clusters available to schedule")
}
var policyName string
if len(binding.OwnerReferences) > 0 {
owner := binding.OwnerReferences[0]
if owner.APIVersion == v1alpha1.SchemeGroupVersion.String() && owner.Kind == "PropagationPolicy" {
policyName = owner.Name
}
}
policy, err := g.policyLister.PropagationPolicies(binding.Namespace).Get(policyName)
if err != nil {
return result, fmt.Errorf("no propagation policy found for <%s/%s>: %v", binding.Namespace, binding.Name, err)
}
feasibleClusters, err := g.findClustersThatFit(ctx, g.scheduleFramework, &policy.Spec.Placement, clusterInfoSnapshot)
if err != nil {
return result, fmt.Errorf("failed findClustersThatFit for <%s/%s>: %v", binding.Namespace, binding.Name, err)
}
if len(feasibleClusters) == 0 {
return result, fmt.Errorf("no clusters fit")
}
klog.V(4).Infof("feasible clusters found for <%s/%s>: %v", binding.Namespace, binding.Name, feasibleClusters)
clustersScore, err := g.prioritizeClusters(ctx, g.scheduleFramework, &policy.Spec.Placement, feasibleClusters)
if err != nil {
return result, fmt.Errorf("failed prioritizeClusters for <%s/%s>: %v", binding.Namespace, binding.Name, err)
}
klog.V(4).Infof("feasible clusters scores for <%s/%s>: %v", binding.Namespace, binding.Name, clustersScore)
clusters := g.selectClusters(clustersScore)
result.SuggestedClusters = clusters
return result, nil
}
// findClustersThatFit finds the clusters that are fit for the placement based on running the filter plugins.
func (g *genericScheduler) findClustersThatFit(
ctx context.Context,
fwk framework.Framework,
placement *v1alpha1.Placement,
clusterInfo *cache.Snapshot) ([]*clusterapi.Cluster, error) {
var out []*clusterapi.Cluster
clusters := clusterInfo.GetClusters()
for _, c := range clusters {
resMap := fwk.RunFilterPlugins(ctx, placement, c.Cluster())
res := resMap.Merge()
if !res.IsSuccess() {
klog.V(4).Infof("cluster %q is not fit", c.Cluster().Name)
} else {
out = append(out, c.Cluster())
}
}
return out, nil
}
// prioritizeClusters prioritize the clusters by running the score plugins.
func (g *genericScheduler) prioritizeClusters(
ctx context.Context,
fwk framework.Framework,
placement *v1alpha1.Placement,
clusters []*clusterapi.Cluster) (result framework.ClusterScoreList, err error) {
scoresMap, err := fwk.RunScorePlugins(ctx, placement, clusters)
if err != nil {
return result, err
}
result = make(framework.ClusterScoreList, len(clusters))
for i := range clusters {
result[i] = framework.ClusterScore{Name: clusters[i].Name, Score: 0}
for j := range scoresMap {
result[i].Score += scoresMap[j][i].Score
}
}
return result, nil
}
// TODO: update the algorithms
func (g *genericScheduler) selectClusters(clustersScore framework.ClusterScoreList) []string {
out := make([]string, len(clustersScore))
for i := range clustersScore {
out[i] = clustersScore[i].Name
}
return out
}