Merge pull request karmada-io#1854 from likakuli/feature_notreadytaint

feat: use taint instead of condition to filter cluster

pkg/apis/cluster/v1alpha1/events.go

@@ -6,4 +6,6 @@ const (
 	EventReasonCreateExecutionSpaceFailed = "CreateExecutionSpaceFailed"
 	// EventReasonRemoveExecutionSpaceFailed indicates that remove execution space failed.
 	EventReasonRemoveExecutionSpaceFailed = "RemoveExecutionSpaceFailed"
+	// EventReasonTaintClusterByConditionFailed indicates that taint cluster by condition
+	EventReasonTaintClusterByConditionFailed = "TaintClusterByCondition"
 )

pkg/controllers/cluster/cluster_controller.go

@@ -40,17 +40,32 @@ const (
 
 var (
 	// UnreachableTaintTemplate is the taint for when a cluster becomes unreachable.
+	// Used for taint based eviction.
 	UnreachableTaintTemplate = &corev1.Taint{
 		Key:    clusterv1alpha1.TaintClusterUnreachable,
 		Effect: corev1.TaintEffectNoExecute,
 	}
 
-	// NotReadyTaintTemplate is the taint for when a cluster is not ready for
-	// executing resources.
+	// UnreachableTaintTemplateForSched is the taint for when a cluster becomes unreachable.
+	// Used for taint based schedule.
+	UnreachableTaintTemplateForSched = &corev1.Taint{
+		Key:    clusterv1alpha1.TaintClusterUnreachable,
+		Effect: corev1.TaintEffectNoSchedule,
+	}
+
+	// NotReadyTaintTemplate is the taint for when a cluster is not ready for executing resources.
+	// Used for taint based eviction.
 	NotReadyTaintTemplate = &corev1.Taint{
 		Key:    clusterv1alpha1.TaintClusterNotReady,
 		Effect: corev1.TaintEffectNoExecute,
 	}
+
+	// NotReadyTaintTemplateForSched is the taint for when a cluster is not ready for executing resources.
+	// Used for taint based schedule.
+	NotReadyTaintTemplateForSched = &corev1.Taint{
+		Key:    clusterv1alpha1.TaintClusterNotReady,
+		Effect: corev1.TaintEffectNoSchedule,
+	}
 )
 
 // Controller is to sync Cluster.
@@ -145,7 +160,7 @@ func (c *Controller) Reconcile(ctx context.Context, req controllerruntime.Reques
 		return c.removeCluster(cluster)
 	}
 
-	return c.syncCluster(cluster)
+	return c.syncCluster(ctx, cluster)
 }
 
 // Start starts an asynchronous loop that monitors the status of cluster.
@@ -173,14 +188,21 @@ func (c *Controller) SetupWithManager(mgr controllerruntime.Manager) error {
 	})
 }
 
-func (c *Controller) syncCluster(cluster *clusterv1alpha1.Cluster) (controllerruntime.Result, error) {
+func (c *Controller) syncCluster(ctx context.Context, cluster *clusterv1alpha1.Cluster) (controllerruntime.Result, error) {
 	// create execution space
 	err := c.createExecutionSpace(cluster)
 	if err != nil {
 		c.EventRecorder.Event(cluster, corev1.EventTypeWarning, fmt.Sprintf("Failed %s", clusterv1alpha1.EventReasonCreateExecutionSpaceFailed), err.Error())
 		return controllerruntime.Result{Requeue: true}, err
 	}
 
+	// taint cluster by condition
+	err = c.taintClusterByCondition(ctx, cluster)
+	if err != nil {
+		c.EventRecorder.Event(cluster, corev1.EventTypeWarning, fmt.Sprintf("Failed %s", clusterv1alpha1.EventReasonTaintClusterByConditionFailed), err.Error())
+		return controllerruntime.Result{Requeue: true}, err
+	}
+
 	// ensure finalizer
 	return c.ensureFinalizer(cluster)
 }
@@ -516,3 +538,28 @@ func (c *Controller) processTaintBaseEviction(ctx context.Context, cluster *clus
 	}
 	return nil
 }
+
+func (c *Controller) taintClusterByCondition(ctx context.Context, cluster *clusterv1alpha1.Cluster) error {
+	currentReadyCondition := meta.FindStatusCondition(cluster.Status.Conditions, clusterv1alpha1.ClusterConditionReady)
+
+	if currentReadyCondition != nil {
+		switch currentReadyCondition.Status {
+		case metav1.ConditionFalse:
+			// Add NotReadyTaintTemplateForSched taint immediately.
+			if err := utilhelper.UpdateClusterControllerTaint(ctx, c.Client, []*corev1.Taint{NotReadyTaintTemplateForSched}, []*corev1.Taint{UnreachableTaintTemplateForSched}, cluster); err != nil {
+				klog.ErrorS(err, "Failed to instantly update UnreachableTaintForSched to NotReadyTaintForSched, will try again in the next cycle.", "cluster", cluster.Name)
+			}
+		case metav1.ConditionUnknown:
+			// Add UnreachableTaintTemplateForSched taint immediately.
+			if err := utilhelper.UpdateClusterControllerTaint(ctx, c.Client, []*corev1.Taint{UnreachableTaintTemplateForSched}, []*corev1.Taint{NotReadyTaintTemplateForSched}, cluster); err != nil {
+				klog.ErrorS(err, "Failed to instantly swap NotReadyTaintForSched to UnreachableTaintForSched, will try again in the next cycle.", "cluster", cluster.Name)
+			}
+		case metav1.ConditionTrue:
+			if err := utilhelper.UpdateClusterControllerTaint(ctx, c.Client, nil, []*corev1.Taint{NotReadyTaintTemplateForSched, UnreachableTaintTemplateForSched}, cluster); err != nil {
+				klog.ErrorS(err, "Failed to remove schedule taints from cluster, will retry in next iteration.", "cluster", cluster.Name)
+			}
+		}
+	}
+
+	return nil
+}

pkg/scheduler/core/generic_scheduler.go

@@ -101,7 +101,8 @@ func (g *genericScheduler) findClustersThatFit(
 	defer metrics.ScheduleStep(metrics.ScheduleStepFilter, time.Now())
 
 	var out []*clusterv1alpha1.Cluster
-	clusters := clusterInfo.GetReadyClusters()
+	// DO NOT filter unhealthy cluster, let users make decisions by using ClusterTolerations of Placement.
+	clusters := clusterInfo.GetClusters()
 	for _, c := range clusters {
 		if result := fwk.RunFilterPlugins(ctx, placement, resource, c.Cluster()); !result.IsSuccess() {
 			klog.V(4).Infof("cluster %q is not fit, reason: %v", c.Cluster().Name, result.AsError())