unify retry logic and add RetryCount and MaxPodRetries

Signed-off-by: Tim Ramlot <[email protected]>

Author: inteon

pkg/apis/prowjobs/v1/types.go

@@ -1053,6 +1053,8 @@ type ProwJobStatus struct {
 	PendingTime *metav1.Time `json:"pendingTime,omitempty"`
 	// CompletionTime is the timestamp for when the job goes to a final state
 	CompletionTime *metav1.Time `json:"completionTime,omitempty"`
+	// Amount of times the Pod was retried.
+	RetryCount int `json:"retryCount,omitempty"`
 	// +kubebuilder:validation:Enum=scheduling;triggered;pending;success;failure;aborted;error
 	// +kubebuilder:validation:Required
 	State       ProwJobState `json:"state,omitempty"`

pkg/plank/reconciler.go

@@ -60,6 +60,8 @@ import (
 
 const ControllerName = "plank"
 
+const MaxPodRetries = 3
+
 // PodStatus constants
 const (
 	Evicted    = "Evicted"
@@ -462,104 +464,57 @@ func (r *reconciler) syncPendingJob(ctx context.Context, pj *prowv1.ProwJob) (*r
 			pj.Status.PodName = pn
 			r.log.WithFields(pjutil.ProwJobFields(pj)).Info("Pod is missing, starting a new pod")
 		}
-	} else if pod.Status.Reason == Evicted {
-		// Pod was evicted.
-		if pj.Spec.ErrorOnEviction {
-			// ErrorOnEviction is enabled, complete the PJ and mark it as
-			// errored.
+	} else if transientFailure := getTransientFailure(pod); transientFailure != PodTransientFailureNone {
+		switch {
+		case transientFailure == PodTransientFailureEvicted && pj.Spec.ErrorOnEviction:
+			// ErrorOnEviction is enabled, complete the PJ and mark it as errored.
 			r.log.WithField("error-on-eviction", true).WithFields(pjutil.ProwJobFields(pj)).Info("Pods Node got evicted, fail job.")
 			pj.SetComplete()
 			pj.Status.State = prowv1.ErrorState
 			pj.Status.Description = "Job pod was evicted by the cluster."
-		} else {
-			// ErrorOnEviction is disabled. Delete the pod now and recreate it in
-			// the next resync.
-			r.log.WithFields(pjutil.ProwJobFields(pj)).Info("Pods Node got evicted, deleting & next sync loop will restart pod")
-			client, ok := r.buildClients[pj.ClusterAlias()]
-			if !ok {
-				return nil, TerminalError(fmt.Errorf("evicted pod %s: unknown cluster alias %q", pod.Name, pj.ClusterAlias()))
-			}
-			if finalizers := sets.New[string](pod.Finalizers...); finalizers.Has(kubernetesreporterapi.FinalizerName) {
-				// We want the end user to not see this, so we have to remove the finalizer, otherwise the pod hangs
-				oldPod := pod.DeepCopy()
-				pod.Finalizers = finalizers.Delete(kubernetesreporterapi.FinalizerName).UnsortedList()
-				if err := client.Patch(ctx, pod, ctrlruntimeclient.MergeFrom(oldPod)); err != nil {
-					return nil, fmt.Errorf("failed to patch pod trying to remove %s finalizer: %w", kubernetesreporterapi.FinalizerName, err)
-				}
-			}
-			r.log.WithField("name", pj.ObjectMeta.Name).Debug("Delete Pod.")
-			return nil, ctrlruntimeclient.IgnoreNotFound(client.Delete(ctx, pod))
-		}
-	} else if isPodTerminated(pod) {
-		// Pod was terminated.
-		if pj.Spec.ErrorOnTermination {
-			// ErrorOnTermination is enabled, complete the PJ and mark it as
-			// errored.
+		case transientFailure == PodTransientFailureTerminated && pj.Spec.ErrorOnTermination:
+			// ErrorOnTermination is enabled, complete the PJ and mark it as errored.
 			r.log.WithField("error-on-termination", true).WithFields(pjutil.ProwJobFields(pj)).Info("Pods Node got terminated, fail job.")
 			pj.SetComplete()
 			pj.Status.State = prowv1.ErrorState
 			pj.Status.Description = "Job pod's node was terminated."
-		} else {
-			// ErrorOnTermination is disabled. Delete the pod now and recreate it in
-			// the next resync.
-			r.log.WithFields(pjutil.ProwJobFields(pj)).Info("Pods Node got terminated, deleting & next sync loop will restart pod")
+		case pj.Status.RetryCount >= MaxPodRetries:
+			// MaxPodRetries is reached, complete the PJ and mark it as errored.
+			r.log.WithField("transient-failure", transientFailure).WithFields(pjutil.ProwJobFields(pj)).Info("Pod Node reached max retries, fail job.")
+			pj.SetComplete()
+			pj.Status.State = prowv1.ErrorState
+			pj.Status.Description = fmt.Sprintf("Job pod reached max retries (%d) for transient failure %s", MaxPodRetries, transientFailure)
+		default:
+			// Update the retry count and delete the pod so it gets recreated in the next resync.
+			pj.Status.RetryCount++
+			r.log.
+				WithField("transientFailure", transientFailure).
+				WithFields(pjutil.ProwJobFields(pj)).
+				Info("Pod has transient failure, deleting & next sync loop will restart pod")
+
 			client, ok := r.buildClients[pj.ClusterAlias()]
 			if !ok {
-				return nil, TerminalError(fmt.Errorf("terminated pod %s: unknown cluster alias %q", pod.Name, pj.ClusterAlias()))
+				return nil, TerminalError(fmt.Errorf("pod %s with transient failure %s: unknown cluster alias %q", pod.Name, transientFailure, pj.ClusterAlias()))
 			}
-			if finalizers := sets.New[string](pod.Finalizers...); finalizers.Has(kubernetesreporterapi.FinalizerName) {
+			if finalizers := sets.New(pod.Finalizers...); finalizers.Has(kubernetesreporterapi.FinalizerName) {
 				// We want the end user to not see this, so we have to remove the finalizer, otherwise the pod hangs
 				oldPod := pod.DeepCopy()
 				pod.Finalizers = finalizers.Delete(kubernetesreporterapi.FinalizerName).UnsortedList()
 				if err := client.Patch(ctx, pod, ctrlruntimeclient.MergeFrom(oldPod)); err != nil {
 					return nil, fmt.Errorf("failed to patch pod trying to remove %s finalizer: %w", kubernetesreporterapi.FinalizerName, err)
 				}
 			}
-			r.log.WithField("name", pj.ObjectMeta.Name).Debug("Delete Pod.")
-			return nil, ctrlruntimeclient.IgnoreNotFound(client.Delete(ctx, pod))
-		}
-	} else if pod.DeletionTimestamp != nil && pod.Status.Reason == NodeUnreachablePodReason {
-		// This can happen in any phase and means the node got evicted after it became unresponsive. Delete the finalizer so the pod
-		// vanishes and we will silently re-create it in the next iteration.
-		r.log.WithFields(pjutil.ProwJobFields(pj)).Info("Pods Node got lost, deleting & next sync loop will restart pod")
-		client, ok := r.buildClients[pj.ClusterAlias()]
-		if !ok {
-			return nil, TerminalError(fmt.Errorf("unknown pod %s: unknown cluster alias %q", pod.Name, pj.ClusterAlias()))
-		}
-
-		if finalizers := sets.New[string](pod.Finalizers...); finalizers.Has(kubernetesreporterapi.FinalizerName) {
-			// We want the end user to not see this, so we have to remove the finalizer, otherwise the pod hangs
-			oldPod := pod.DeepCopy()
-			pod.Finalizers = finalizers.Delete(kubernetesreporterapi.FinalizerName).UnsortedList()
-			if err := client.Patch(ctx, pod, ctrlruntimeclient.MergeFrom(oldPod)); err != nil {
-				return nil, fmt.Errorf("failed to patch pod trying to remove %s finalizer: %w", kubernetesreporterapi.FinalizerName, err)
-			}
-		}
 
-		return nil, nil
-	} else {
-		switch pod.Status.Phase {
-		case corev1.PodUnknown:
-			// Pod is in Unknown state. This can happen if there is a problem with
-			// the node. Delete the old pod, this will fire an event that triggers
-			// a new reconciliation in which we will re-create the pod.
-			r.log.WithFields(pjutil.ProwJobFields(pj)).Info("Pod is in unknown state, deleting & restarting pod")
-			client, ok := r.buildClients[pj.ClusterAlias()]
-			if !ok {
-				return nil, TerminalError(fmt.Errorf("unknown pod %s: unknown cluster alias %q", pod.Name, pj.ClusterAlias()))
+			// Pod is already deleted, so we don't need to delete it again.
+			if pod.DeletionTimestamp != nil {
+				return nil, nil
 			}
 
-			if finalizers := sets.New[string](pod.Finalizers...); finalizers.Has(kubernetesreporterapi.FinalizerName) {
-				// We want the end user to not see this, so we have to remove the finalizer, otherwise the pod hangs
-				oldPod := pod.DeepCopy()
-				pod.Finalizers = finalizers.Delete(kubernetesreporterapi.FinalizerName).UnsortedList()
-				if err := client.Patch(ctx, pod, ctrlruntimeclient.MergeFrom(oldPod)); err != nil {
-					return nil, fmt.Errorf("failed to patch pod trying to remove %s finalizer: %w", kubernetesreporterapi.FinalizerName, err)
-				}
-			}
 			r.log.WithField("name", pj.ObjectMeta.Name).Debug("Delete Pod.")
 			return nil, ctrlruntimeclient.IgnoreNotFound(client.Delete(ctx, pod))
-
+		}
+	} else {
+		switch pod.Status.Phase {
 		case corev1.PodSucceeded:
 			pj.SetComplete()
 			// There were bugs around this in the past so be paranoid and verify each container
@@ -701,31 +656,53 @@ func (r *reconciler) syncPendingJob(ctx context.Context, pj *prowv1.ProwJob) (*r
 	return nil, nil
 }
 
-func isPodTerminated(pod *corev1.Pod) bool {
+type PodTransientFailure string
+
+const (
+	PodTransientFailureNone        PodTransientFailure = ""
+	PodTransientFailureUnknown     PodTransientFailure = "unknown"
+	PodTransientFailureEvicted     PodTransientFailure = "evicted"
+	PodTransientFailureTerminated  PodTransientFailure = "terminated"
+	PodTransientFailureUnreachable PodTransientFailure = "unreachable"
+)
+
+func getTransientFailure(pod *corev1.Pod) PodTransientFailure {
+	if pod.Status.Reason == Evicted {
+		return PodTransientFailureEvicted
+	}
+
 	// If there was a Graceful node shutdown, the Pod's status will have a
 	// reason set to "Terminated":
 	// https://kubernetes.io/docs/concepts/architecture/nodes/#graceful-node-shutdown
 	if pod.Status.Reason == Terminated {
-		return true
+		return PodTransientFailureTerminated
 	}
 
 	for _, condition := range pod.Status.Conditions {
 		// If the node does no longer exist and the pod gets garbage collected,
 		// this condition will be set:
 		// https://kubernetes.io/docs/concepts/workloads/pods/disruptions/#pod-disruption-conditions
 		if condition.Reason == "DeletionByPodGC" {
-			return true
+			return PodTransientFailureTerminated
 		}
 
 		// On GCP, before a new spot instance is started, the old pods are garbage
 		// collected (if they have not been already by the Kubernetes PodGC):
 		// https://github.com/kubernetes/cloud-provider-gcp/blob/25e5dcc715781316bc5e39f8b17c0d5b313453f7/cmd/gcp-controller-manager/node_csr_approver.go#L1035-L1058
 		if condition.Reason == "DeletionByGCPControllerManager" {
-			return true
+			return PodTransientFailureTerminated
 		}
 	}
 
-	return false
+	if pod.Status.Reason == NodeUnreachablePodReason && pod.DeletionTimestamp != nil {
+		return PodTransientFailureUnreachable
+	}
+
+	if pod.Status.Phase == corev1.PodUnknown {
+		return PodTransientFailureUnknown
+	}
+
+	return PodTransientFailureNone
 }
 
 // syncTriggeredJob syncs jobs that do not yet have an associated test workload running