Golang deployment.GetAvailablePodsForReplicaSets函数代码示例

// cleanupUnhealthyReplicas will scale down old replica sets with unhealthy replicas, so that all unhealthy replicas will be deleted.
func (dc *DeploymentController) cleanupUnhealthyReplicas(oldRSs []*extensions.ReplicaSet, deployment extensions.Deployment, maxCleanupCount int) (int, error) {
	sort.Sort(controller.ReplicaSetsByCreationTimestamp(oldRSs))
	// Safely scale down all old replica sets with unhealthy replicas. Replica set will sort the pods in the order
	// such that not-ready < ready, unscheduled < scheduled, and pending < running. This ensures that unhealthy replicas will
	// been deleted first and won't increase unavailability.
	totalScaledDown := 0
	for _, targetRS := range oldRSs {
		if totalScaledDown >= maxCleanupCount {
			break
		}
		if targetRS.Spec.Replicas == 0 {
			// cannot scale down this replica set.
			continue
		}
		readyPodCount, err := deploymentutil.GetAvailablePodsForReplicaSets(dc.client, []*extensions.ReplicaSet{targetRS}, 0)
		if err != nil {
			return totalScaledDown, fmt.Errorf("could not find available pods: %v", err)
		}
		if targetRS.Spec.Replicas == readyPodCount {
			// no unhealthy replicas found, no scaling required.
			continue
		}

		scaledDownCount := integer.IntMin(maxCleanupCount-totalScaledDown, targetRS.Spec.Replicas-readyPodCount)
		newReplicasCount := targetRS.Spec.Replicas - scaledDownCount
		_, _, err = dc.scaleReplicaSetAndRecordEvent(targetRS, newReplicasCount, deployment)
		if err != nil {
			return totalScaledDown, err
		}
		totalScaledDown += scaledDownCount
	}
	return totalScaledDown, nil
}

func (dc *DeploymentController) calculateStatus(allRSs []*extensions.ReplicaSet, newRS *extensions.ReplicaSet, deployment extensions.Deployment) (totalReplicas, updatedReplicas, availableReplicas, unavailableReplicas int, err error) {
	totalReplicas = deploymentutil.GetReplicaCountForReplicaSets(allRSs)
	updatedReplicas = deploymentutil.GetReplicaCountForReplicaSets([]*extensions.ReplicaSet{newRS})
	minReadySeconds := deployment.Spec.MinReadySeconds
	availableReplicas, err = deploymentutil.GetAvailablePodsForReplicaSets(dc.client, allRSs, minReadySeconds)
	if err != nil {
		err = fmt.Errorf("failed to count available pods: %v", err)
		return
	}
	unavailableReplicas = totalReplicas - availableReplicas
	return
}

// scaleDownOldReplicaSetsForRollingUpdate scales down old replica sets when deployment strategy is "RollingUpdate".
// Need check maxUnavailable to ensure availability
func (dc *DeploymentController) scaleDownOldReplicaSetsForRollingUpdate(allRSs []*extensions.ReplicaSet, oldRSs []*extensions.ReplicaSet, deployment extensions.Deployment) (int, error) {
	maxUnavailable, isPercent, err := util.GetIntOrPercentValue(&deployment.Spec.Strategy.RollingUpdate.MaxUnavailable)
	if err != nil {
		return 0, fmt.Errorf("invalid value for MaxUnavailable: %v", err)
	}
	if isPercent {
		maxUnavailable = util.GetValueFromPercent(maxUnavailable, deployment.Spec.Replicas)
	}
	// Check if we can scale down.
	minAvailable := deployment.Spec.Replicas - maxUnavailable
	minReadySeconds := deployment.Spec.MinReadySeconds
	// Find the number of ready pods.
	readyPodCount, err := deploymentutil.GetAvailablePodsForReplicaSets(dc.client, allRSs, minReadySeconds)
	if err != nil {
		return 0, fmt.Errorf("could not find available pods: %v", err)
	}
	if readyPodCount <= minAvailable {
		// Cannot scale down.
		return 0, nil
	}

	sort.Sort(controller.ReplicaSetsByCreationTimestamp(oldRSs))

	totalScaledDown := 0
	totalScaleDownCount := readyPodCount - minAvailable
	for _, targetRS := range oldRSs {
		if totalScaledDown >= totalScaleDownCount {
			// No further scaling required.
			break
		}
		if targetRS.Spec.Replicas == 0 {
			// cannot scale down this ReplicaSet.
			continue
		}
		// Scale down.
		scaleDownCount := int(math.Min(float64(targetRS.Spec.Replicas), float64(totalScaleDownCount-totalScaledDown)))
		newReplicasCount := targetRS.Spec.Replicas - scaleDownCount
		_, err = dc.scaleReplicaSetAndRecordEvent(targetRS, newReplicasCount, deployment)
		if err != nil {
			return totalScaledDown, err
		}

		totalScaledDown += scaleDownCount
	}

	return totalScaledDown, nil
}

// scaleDownOldReplicaSetsForRollingUpdate scales down old replica sets when deployment strategy is "RollingUpdate".
// Need check maxUnavailable to ensure availability
func (dc *DeploymentController) scaleDownOldReplicaSetsForRollingUpdate(allRSs []*extensions.ReplicaSet, oldRSs []*extensions.ReplicaSet, deployment *extensions.Deployment) (int32, error) {
	maxUnavailable := maxUnavailable(*deployment)

	// Check if we can scale down.
	minAvailable := deployment.Spec.Replicas - maxUnavailable
	minReadySeconds := deployment.Spec.MinReadySeconds
	// Find the number of ready pods.
	// TODO: use dc.getAvailablePodsForReplicaSets instead
	availablePodCount, err := deploymentutil.GetAvailablePodsForReplicaSets(dc.client, deployment, allRSs, minReadySeconds)
	if err != nil {
		return 0, fmt.Errorf("could not find available pods: %v", err)
	}
	if availablePodCount <= minAvailable {
		// Cannot scale down.
		return 0, nil
	}
	glog.V(4).Infof("Found %d available pods in deployment %s, scaling down old RSes", availablePodCount, deployment.Name)

	sort.Sort(controller.ReplicaSetsByCreationTimestamp(oldRSs))

	totalScaledDown := int32(0)
	totalScaleDownCount := availablePodCount - minAvailable
	for _, targetRS := range oldRSs {
		if totalScaledDown >= totalScaleDownCount {
			// No further scaling required.
			break
		}
		if targetRS.Spec.Replicas == 0 {
			// cannot scale down this ReplicaSet.
			continue
		}
		// Scale down.
		scaleDownCount := int32(integer.IntMin(int(targetRS.Spec.Replicas), int(totalScaleDownCount-totalScaledDown)))
		newReplicasCount := targetRS.Spec.Replicas - scaleDownCount
		if newReplicasCount > targetRS.Spec.Replicas {
			return 0, fmt.Errorf("when scaling down old RS, got invalid request to scale down %s/%s %d -> %d", targetRS.Namespace, targetRS.Name, targetRS.Spec.Replicas, newReplicasCount)
		}
		_, _, err = dc.scaleReplicaSetAndRecordEvent(targetRS, newReplicasCount, deployment)
		if err != nil {
			return totalScaledDown, err
		}

		totalScaledDown += scaleDownCount
	}

	return totalScaledDown, nil
}

// cleanupUnhealthyReplicas will scale down old replica sets with unhealthy replicas, so that all unhealthy replicas will be deleted.
func (dc *DeploymentController) cleanupUnhealthyReplicas(oldRSs []*extensions.ReplicaSet, deployment *extensions.Deployment, minReadySeconds, maxCleanupCount int32) ([]*extensions.ReplicaSet, int32, error) {
	sort.Sort(controller.ReplicaSetsByCreationTimestamp(oldRSs))
	// Safely scale down all old replica sets with unhealthy replicas. Replica set will sort the pods in the order
	// such that not-ready < ready, unscheduled < scheduled, and pending < running. This ensures that unhealthy replicas will
	// been deleted first and won't increase unavailability.
	totalScaledDown := int32(0)
	for i, targetRS := range oldRSs {
		if totalScaledDown >= maxCleanupCount {
			break
		}
		if targetRS.Spec.Replicas == 0 {
			// cannot scale down this replica set.
			continue
		}
		// TODO: use dc.getAvailablePodsForReplicaSets instead
		availablePodCount, err := deploymentutil.GetAvailablePodsForReplicaSets(dc.client, deployment, []*extensions.ReplicaSet{targetRS}, minReadySeconds)
		if err != nil {
			return nil, totalScaledDown, fmt.Errorf("could not find available pods: %v", err)
		}
		if targetRS.Spec.Replicas == availablePodCount {
			// no unhealthy replicas found, no scaling required.
			continue
		}

		scaledDownCount := int32(integer.IntMin(int(maxCleanupCount-totalScaledDown), int(targetRS.Spec.Replicas-availablePodCount)))
		newReplicasCount := targetRS.Spec.Replicas - scaledDownCount
		if newReplicasCount > targetRS.Spec.Replicas {
			return nil, 0, fmt.Errorf("when cleaning up unhealthy replicas, got invalid request to scale down %s/%s %d -> %d", targetRS.Namespace, targetRS.Name, targetRS.Spec.Replicas, newReplicasCount)
		}
		_, updatedOldRS, err := dc.scaleReplicaSetAndRecordEvent(targetRS, newReplicasCount, deployment)
		if err != nil {
			return nil, totalScaledDown, err
		}
		totalScaledDown += scaledDownCount
		oldRSs[i] = updatedOldRS
	}
	return oldRSs, totalScaledDown, nil
}

// Set expectationsCheck to false to bypass expectations check when testing
func (dc *DeploymentController) reconcileOldReplicaSets(allRSs []*extensions.ReplicaSet, oldRSs []*extensions.ReplicaSet, newRS *extensions.ReplicaSet, deployment extensions.Deployment, expectationsCheck bool) (bool, error) {
	oldPodsCount := deploymentutil.GetReplicaCountForReplicaSets(oldRSs)
	if oldPodsCount == 0 {
		// Can't scale down further
		return false, nil
	}

	// Check the expectations of deployment before reconciling
	dKey, err := controller.KeyFunc(&deployment)
	if err != nil {
		return false, fmt.Errorf("Couldn't get key for deployment %#v: %v", deployment, err)
	}
	if expectationsCheck && !dc.podExpectations.SatisfiedExpectations(dKey) {
		glog.V(4).Infof("Pod expectations not met yet before reconciling old replica sets\n")
		return false, nil
	}

	minReadySeconds := deployment.Spec.MinReadySeconds
	allPodsCount := deploymentutil.GetReplicaCountForReplicaSets(allRSs)
	newRSAvailablePodCount, err := deploymentutil.GetAvailablePodsForReplicaSets(dc.client, []*extensions.ReplicaSet{newRS}, minReadySeconds)
	if err != nil {
		return false, fmt.Errorf("could not find available pods: %v", err)
	}

	maxUnavailable, err := intstrutil.GetValueFromIntOrPercent(&deployment.Spec.Strategy.RollingUpdate.MaxUnavailable, deployment.Spec.Replicas)
	if err != nil {
		return false, err
	}

	// Check if we can scale down. We can scale down in the following 2 cases:
	// * Some old replica sets have unhealthy replicas, we could safely scale down those unhealthy replicas since that won't further
	//  increase unavailability.
	// * New replica set has scaled up and it's replicas becomes ready, then we can scale down old replica sets in a further step.
	//
	// maxScaledDown := allPodsCount - minAvailable - newReplicaSetPodsUnavailable
	// take into account not only maxUnavailable and any surge pods that have been created, but also unavailable pods from
	// the newRS, so that the unavailable pods from the newRS would not make us scale down old replica sets in a further
	// step(that will increase unavailability).
	//
	// Concrete example:
	//
	// * 10 replicas
	// * 2 maxUnavailable (absolute number, not percent)
	// * 3 maxSurge (absolute number, not percent)
	//
	// case 1:
	// * Deployment is updated, newRS is created with 3 replicas, oldRS is scaled down to 8, and newRS is scaled up to 5.
	// * The new replica set pods crashloop and never become available.
	// * allPodsCount is 13. minAvailable is 8. newRSPodsUnavailable is 5.
	// * A node fails and causes one of the oldRS pods to become unavailable. However, 13 - 8 - 5 = 0, so the oldRS won't be scaled down.
	// * The user notices the crashloop and does kubectl rollout undo to rollback.
	// * newRSPodsUnavailable is 1, since we rolled back to the good replica set, so maxScaledDown = 13 - 8 - 1 = 4. 4 of the crashlooping pods will be scaled down.
	// * The total number of pods will then be 9 and the newRS can be scaled up to 10.
	//
	// case 2:
	// Same example, but pushing a new pod template instead of rolling back (aka "roll over"):
	// * The new replica set created must start with 0 replicas because allPodsCount is already at 13.
	// * However, newRSPodsUnavailable would also be 0, so the 2 old replica sets could be scaled down by 5 (13 - 8 - 0), which would then
	// allow the new replica set to be scaled up by 5.
	minAvailable := deployment.Spec.Replicas - maxUnavailable
	newRSUnavailablePodCount := newRS.Spec.Replicas - newRSAvailablePodCount
	maxScaledDown := allPodsCount - minAvailable - newRSUnavailablePodCount
	if maxScaledDown <= 0 {
		return false, nil
	}

	// Clean up unhealthy replicas first, otherwise unhealthy replicas will block deployment
	// and cause timeout. See https://github.com/kubernetes/kubernetes/issues/16737
	cleanupCount, err := dc.cleanupUnhealthyReplicas(oldRSs, deployment, maxScaledDown)
	if err != nil {
		return false, nil
	}

	// Scale down old replica sets, need check maxUnavailable to ensure we can scale down
	scaledDownCount, err := dc.scaleDownOldReplicaSetsForRollingUpdate(allRSs, oldRSs, deployment)
	if err != nil {
		return false, nil
	}

	totalScaledDown := cleanupCount + scaledDownCount
	if expectationsCheck {
		dc.podExpectations.ExpectDeletions(dKey, totalScaledDown)
	}

	return totalScaledDown > 0, nil
}