controller: proportionally scale paused and rolling deployments

hack/test-cmd.sh

@@ -1772,35 +1772,35 @@ __EOF__
   # Command
   # Create a deployment (revision 1)
   kubectl create -f hack/testdata/deployment-revision1.yaml "${kube_flags[@]}"
-  kube::test::get_object_assert deployment "{{range.items}}{{$id_field}}:{{end}}" 'nginx-deployment:'
+  kube::test::get_object_assert deployment "{{range.items}}{{$id_field}}:{{end}}" 'nginx:'
   kube::test::get_object_assert deployment "{{range.items}}{{$deployment_image_field}}:{{end}}" "${IMAGE_DEPLOYMENT_R1}:"
   # Rollback to revision 1 - should be no-op
-  kubectl rollout undo deployment nginx-deployment --to-revision=1 "${kube_flags[@]}"
+  kubectl rollout undo deployment nginx --to-revision=1 "${kube_flags[@]}"
   kube::test::get_object_assert deployment "{{range.items}}{{$deployment_image_field}}:{{end}}" "${IMAGE_DEPLOYMENT_R1}:"
   # Update the deployment (revision 2)
   kubectl apply -f hack/testdata/deployment-revision2.yaml "${kube_flags[@]}"
   kube::test::get_object_assert deployment.extensions "{{range.items}}{{$deployment_image_field}}:{{end}}" "${IMAGE_DEPLOYMENT_R2}:"
   # Rollback to revision 1
-  kubectl rollout undo deployment nginx-deployment --to-revision=1 "${kube_flags[@]}"
+  kubectl rollout undo deployment nginx --to-revision=1 "${kube_flags[@]}"
   sleep 1
   kube::test::get_object_assert deployment "{{range.items}}{{$deployment_image_field}}:{{end}}" "${IMAGE_DEPLOYMENT_R1}:"
   # Rollback to revision 1000000 - should be no-op
-  kubectl rollout undo deployment nginx-deployment --to-revision=1000000 "${kube_flags[@]}"
+  kubectl rollout undo deployment nginx --to-revision=1000000 "${kube_flags[@]}"
   kube::test::get_object_assert deployment "{{range.items}}{{$deployment_image_field}}:{{end}}" "${IMAGE_DEPLOYMENT_R1}:"
   # Rollback to last revision
-  kubectl rollout undo deployment nginx-deployment "${kube_flags[@]}"
+  kubectl rollout undo deployment nginx "${kube_flags[@]}"
   sleep 1
   kube::test::get_object_assert deployment "{{range.items}}{{$deployment_image_field}}:{{end}}" "${IMAGE_DEPLOYMENT_R2}:"
   # Pause the deployment
-  kubectl-with-retry rollout pause deployment nginx-deployment "${kube_flags[@]}"
+  kubectl-with-retry rollout pause deployment nginx "${kube_flags[@]}"
   # A paused deployment cannot be rolled back
-  ! kubectl rollout undo deployment nginx-deployment "${kube_flags[@]}"
+  ! kubectl rollout undo deployment nginx "${kube_flags[@]}"
   # Resume the deployment
-  kubectl-with-retry rollout resume deployment nginx-deployment "${kube_flags[@]}"
+  kubectl-with-retry rollout resume deployment nginx "${kube_flags[@]}"
   # The resumed deployment can now be rolled back
-  kubectl rollout undo deployment nginx-deployment "${kube_flags[@]}"
+  kubectl rollout undo deployment nginx "${kube_flags[@]}"
   # Clean up
-  kubectl delete deployment nginx-deployment "${kube_flags[@]}"
+  kubectl delete deployment nginx "${kube_flags[@]}"
 
   ### Set image of a deployment 
   # Pre-condition: no deployment exists

hack/testdata/deployment-revision1.yaml

 apiVersion: extensions/v1beta1
 kind: Deployment
 metadata:
-  name: nginx-deployment
+  name: nginx
   labels:
-    name: nginx-deployment
+    name: nginx-undo
 spec:
   replicas: 3
   selector:
     matchLabels:
-      name: nginx
+      name: nginx-undo
   template:
     metadata:
       labels:
-        name: nginx
+        name: nginx-undo
     spec:
       containers:
       - name: nginx

hack/testdata/deployment-revision2.yaml

 apiVersion: extensions/v1beta1
 kind: Deployment
 metadata:
-  name: nginx-deployment
+  name: nginx
   labels:
-    name: nginx-deployment
+    name: nginx-undo
 spec:
   replicas: 3
   selector:
     matchLabels:
-      name: nginx
+      name: nginx-undo
   template:
     metadata:
       labels:
-        name: nginx
+        name: nginx-undo
     spec:
       containers:
       - name: nginx

pkg/apis/extensions/validation/validation.go

@@ -147,12 +147,15 @@ var ValidateDeploymentName = apivalidation.NameIsDNSSubdomain
 
 func ValidatePositiveIntOrPercent(intOrPercent intstr.IntOrString, fldPath *field.Path) field.ErrorList {
 	allErrs := field.ErrorList{}
-	if intOrPercent.Type == intstr.String {
+	switch intOrPercent.Type {
+	case intstr.String:
 		if !validation.IsValidPercent(intOrPercent.StrVal) {
-			allErrs = append(allErrs, field.Invalid(fldPath, intOrPercent, "must be an integer or percentage (e.g '5%')"))
+			allErrs = append(allErrs, field.Invalid(fldPath, intOrPercent, "must be an integer or percentage (e.g '5%%')"))
 		}
-	} else if intOrPercent.Type == intstr.Int {
+	case intstr.Int:
 		allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(intOrPercent.IntValue()), fldPath)...)
+	default:
+		allErrs = append(allErrs, field.Invalid(fldPath, intOrPercent, "must be an integer or percentage (e.g '5%%')"))
 	}
 	return allErrs
 }

pkg/controller/controller_utils.go

@@ -619,7 +619,9 @@ func IsPodActive(p api.Pod) bool {
 func FilterActiveReplicaSets(replicaSets []*extensions.ReplicaSet) []*extensions.ReplicaSet {
 	active := []*extensions.ReplicaSet{}
 	for i := range replicaSets {
-		if replicaSets[i].Spec.Replicas > 0 {
+		rs := replicaSets[i]
+
+		if rs != nil && rs.Spec.Replicas > 0 {
 			active = append(active, replicaSets[i])
 		}
 	}
@@ -639,7 +641,6 @@ type ControllersByCreationTimestamp []*api.ReplicationController
 
 func (o ControllersByCreationTimestamp) Len() int      { return len(o) }
 func (o ControllersByCreationTimestamp) Swap(i, j int) { o[i], o[j] = o[j], o[i] }
-
 func (o ControllersByCreationTimestamp) Less(i, j int) bool {
 	if o[i].CreationTimestamp.Equal(o[j].CreationTimestamp) {
 		return o[i].Name < o[j].Name
@@ -647,15 +648,40 @@ func (o ControllersByCreationTimestamp) Less(i, j int) bool {
 	return o[i].CreationTimestamp.Before(o[j].CreationTimestamp)
 }
 
-// ReplicaSetsByCreationTimestamp sorts a list of ReplicationSets by creation timestamp, using their names as a tie breaker.
+// ReplicaSetsByCreationTimestamp sorts a list of ReplicaSet by creation timestamp, using their names as a tie breaker.
 type ReplicaSetsByCreationTimestamp []*extensions.ReplicaSet
 
 func (o ReplicaSetsByCreationTimestamp) Len() int      { return len(o) }
 func (o ReplicaSetsByCreationTimestamp) Swap(i, j int) { o[i], o[j] = o[j], o[i] }
-
 func (o ReplicaSetsByCreationTimestamp) Less(i, j int) bool {
 	if o[i].CreationTimestamp.Equal(o[j].CreationTimestamp) {
 		return o[i].Name < o[j].Name
 	}
 	return o[i].CreationTimestamp.Before(o[j].CreationTimestamp)
 }
+
+// ReplicaSetsBySizeOlder sorts a list of ReplicaSet by size in descending order, using their creation timestamp or name as a tie breaker.
+// By using the creation timestamp, this sorts from old to new replica sets.
+type ReplicaSetsBySizeOlder []*extensions.ReplicaSet
+
+func (o ReplicaSetsBySizeOlder) Len() int      { return len(o) }
+func (o ReplicaSetsBySizeOlder) Swap(i, j int) { o[i], o[j] = o[j], o[i] }
+func (o ReplicaSetsBySizeOlder) Less(i, j int) bool {
+	if o[i].Spec.Replicas == o[j].Spec.Replicas {
+		return ReplicaSetsByCreationTimestamp(o).Less(i, j)
+	}
+	return o[i].Spec.Replicas > o[j].Spec.Replicas
+}
+
+// ReplicaSetsBySizeNewer sorts a list of ReplicaSet by size in descending order, using their creation timestamp or name as a tie breaker.
+// By using the creation timestamp, this sorts from new to old replica sets.
+type ReplicaSetsBySizeNewer []*extensions.ReplicaSet
+
+func (o ReplicaSetsBySizeNewer) Len() int      { return len(o) }
+func (o ReplicaSetsBySizeNewer) Swap(i, j int) { o[i], o[j] = o[j], o[i] }
+func (o ReplicaSetsBySizeNewer) Less(i, j int) bool {
+	if o[i].Spec.Replicas == o[j].Spec.Replicas {
+		return ReplicaSetsByCreationTimestamp(o).Less(j, i)
+	}
+	return o[i].Spec.Replicas > o[j].Spec.Replicas
+}

pkg/controller/deployment/util.go

+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package deployment
+
+import (
+	"fmt"
+	"sort"
+	"strconv"
+
+	"github.com/golang/glog"
+
+	"k8s.io/kubernetes/pkg/apis/extensions"
+	"k8s.io/kubernetes/pkg/controller"
+	deploymentutil "k8s.io/kubernetes/pkg/util/deployment"
+	"k8s.io/kubernetes/pkg/util/integer"
+)
+
+// findActiveOrLatest returns the only active or the latest replica set in case there is at most one active
+// replica set. If there are more active replica sets, then we should proportionally scale them.
+func findActiveOrLatest(newRS *extensions.ReplicaSet, oldRSs []*extensions.ReplicaSet) *extensions.ReplicaSet {
+	if newRS == nil && len(oldRSs) == 0 {
+		return nil
+	}
+
+	sort.Sort(sort.Reverse(controller.ReplicaSetsByCreationTimestamp(oldRSs)))
+	allRSs := controller.FilterActiveReplicaSets(append(oldRSs, newRS))
+
+	switch len(allRSs) {
+	case 0:
+		// If there is no active replica set then we should return the newest.
+		if newRS != nil {
+			return newRS
+		}
+		return oldRSs[0]
+	case 1:
+		return allRSs[0]
+	default:
+		return nil
+	}
+}
+
+func getDesiredReplicasAnnotation(rs *extensions.ReplicaSet) (int32, bool) {
+	return getIntFromAnnotation(rs, deploymentutil.DesiredReplicasAnnotation)
+}
+
+func getMaxReplicasAnnotation(rs *extensions.ReplicaSet) (int32, bool) {
+	return getIntFromAnnotation(rs, deploymentutil.MaxReplicasAnnotation)
+}
+
+func getIntFromAnnotation(rs *extensions.ReplicaSet, annotationKey string) (int32, bool) {
+	annotationValue, ok := rs.Annotations[annotationKey]
+	if !ok {
+		return int32(0), false
+	}
+	intValue, err := strconv.Atoi(annotationValue)
+	if err != nil {
+		glog.Warningf("Cannot convert the value %q with annotation key %q for the replica set %q",
+			annotationValue, annotationKey, rs.Name)
+		return int32(0), false
+	}
+	return int32(intValue), true
+}
+
+func setReplicasAnnotations(rs *extensions.ReplicaSet, desiredReplicas, maxReplicas int32) bool {
+	updated := false
+	if rs.Annotations == nil {
+		rs.Annotations = make(map[string]string)
+	}
+	desiredString := fmt.Sprintf("%d", desiredReplicas)
+	if hasString := rs.Annotations[deploymentutil.DesiredReplicasAnnotation]; hasString != desiredString {
+		rs.Annotations[deploymentutil.DesiredReplicasAnnotation] = desiredString
+		updated = true
+	}
+	maxString := fmt.Sprintf("%d", maxReplicas)
+	if hasString := rs.Annotations[deploymentutil.MaxReplicasAnnotation]; hasString != maxString {
+		rs.Annotations[deploymentutil.MaxReplicasAnnotation] = maxString
+		updated = true
+	}
+	return updated
+}
+
+// maxUnavailable returns the maximum unavailable pods a rolling deployment can take.
+func maxUnavailable(deployment extensions.Deployment) int32 {
+	if !deploymentutil.IsRollingUpdate(&deployment) {
+		return int32(0)
+	}
+	// Error caught by validation
+	_, maxUnavailable, _ := deploymentutil.ResolveFenceposts(&deployment.Spec.Strategy.RollingUpdate.MaxSurge, &deployment.Spec.Strategy.RollingUpdate.MaxUnavailable, deployment.Spec.Replicas)
+	return maxUnavailable
+}
+
+// maxSurge returns the maximum surge pods a rolling deployment can take.
+func maxSurge(deployment extensions.Deployment) int32 {
+	if !deploymentutil.IsRollingUpdate(&deployment) {
+		return int32(0)
+	}
+	// Error caught by validation
+	maxSurge, _, _ := deploymentutil.ResolveFenceposts(&deployment.Spec.Strategy.RollingUpdate.MaxSurge, &deployment.Spec.Strategy.RollingUpdate.MaxUnavailable, deployment.Spec.Replicas)
+	return maxSurge
+}
+
+// getProportion will estimate the proportion for the provided replica set using 1. the current size
+// of the parent deployment, 2. the replica count that needs be added on the replica sets of the
+// deployment, and 3. the total replicas added in the replica sets of the deployment so far.
+func getProportion(rs *extensions.ReplicaSet, d extensions.Deployment, deploymentReplicasToAdd, deploymentReplicasAdded int32) int32 {
+	if rs == nil || rs.Spec.Replicas == 0 || deploymentReplicasToAdd == 0 || deploymentReplicasToAdd == deploymentReplicasAdded {
+		return int32(0)
+	}
+
+	rsFraction := getReplicaSetFraction(*rs, d)
+	allowed := deploymentReplicasToAdd - deploymentReplicasAdded
+
+	if deploymentReplicasToAdd > 0 {
+		// Use the minimum between the replica set fraction and the maximum allowed replicas
+		// when scaling up. This way we ensure we will not scale up more than the allowed
+		// replicas we can add.
+		return integer.Int32Min(rsFraction, allowed)
+	}
+	// Use the maximum between the replica set fraction and the maximum allowed replicas
+	// when scaling down. This way we ensure we will not scale down more than the allowed
+	// replicas we can remove.
+	return integer.Int32Max(rsFraction, allowed)
+}
+
+// getReplicaSetFraction estimates the fraction of replicas a replica set can have in
+// 1. a scaling event during a rollout or 2. when scaling a paused deployment.
+func getReplicaSetFraction(rs extensions.ReplicaSet, d extensions.Deployment) int32 {
+	// If we are scaling down to zero then the fraction of this replica set is its whole size (negative)
+	if d.Spec.Replicas == int32(0) {
+		return -rs.Spec.Replicas
+	}
+
+	deploymentReplicas := d.Spec.Replicas + maxSurge(d)
+	annotatedReplicas, ok := getMaxReplicasAnnotation(&rs)
+	if !ok {
+		// If we cannot find the annotation then fallback to the current deployment size. Note that this
+		// will not be an accurate proportion estimation in case other replica sets have different values
+		// which means that the deployment was scaled at some point but we at least will stay in limits
+		// due to the min-max comparisons in getProportion.
+		annotatedReplicas = d.Status.Replicas
+	}
+
+	// We should never proportionally scale up from zero which means rs.spec.replicas and annotatedReplicas
+	// will never be zero here.
+	newRSsize := (float64(rs.Spec.Replicas * deploymentReplicas)) / float64(annotatedReplicas)
+	return integer.RoundToInt32(newRSsize) - rs.Spec.Replicas
+}

pkg/util/deployment/deployment.go

@@ -41,6 +41,14 @@ import (
 const (
 	// The revision annotation of a deployment's replica sets which records its rollout sequence
 	RevisionAnnotation = "deployment.kubernetes.io/revision"
+	// DesiredReplicasAnnotation is the desired replicas for a deployment recorded as an annotation
+	// in its replica sets. Helps in separating scaling events from the rollout process and for
+	// determining if the new replica set for a deployment is really saturated.
+	DesiredReplicasAnnotation = "deployment.kubernetes.io/desired-replicas"
+	// MaxReplicasAnnotation is the maximum replicas a deployment can have at a given point, which
+	// is deployment.spec.replicas + maxSurge. Used by the underlying replica sets to estimate their
+	// proportions in case the deployment has surge replicas.
+	MaxReplicasAnnotation = "deployment.kubernetes.io/max-replicas"
 
 	// Here are the possible rollback event reasons
 	RollbackRevisionNotFound  = "DeploymentRollbackRevisionNotFound"
@@ -434,6 +442,21 @@ func NewRSNewReplicas(deployment *extensions.Deployment, allRSs []*extensions.Re
 	}
 }
 
+// IsSaturated checks if the new replica set is saturated by comparing its size with its deployment size.
+// Both the deployment and the replica set have to believe this replica set can own all of the desired
+// replicas in the deployment and the annotation helps in achieving that.
+func IsSaturated(deployment *extensions.Deployment, rs *extensions.ReplicaSet) bool {
+	if rs == nil {
+		return false
+	}
+	desiredString := rs.Annotations[DesiredReplicasAnnotation]
+	desired, err := strconv.Atoi(desiredString)
+	if err != nil {
+		return false
+	}
+	return rs.Spec.Replicas == deployment.Spec.Replicas && int32(desired) == deployment.Spec.Replicas
+}
+
 // Polls for deployment to be updated so that deployment.Status.ObservedGeneration >= desiredGeneration.
 // Returns error if polling timesout.
 func WaitForObservedDeployment(getDeploymentFunc func() (*extensions.Deployment, error), desiredGeneration int64, interval, timeout time.Duration) error {

pkg/util/intstr/intstr.go

@@ -144,5 +144,5 @@ func getIntOrPercentValue(intOrStr *IntOrString) (int, bool, error) {
 		}
 		return int(v), true, nil
 	}
-	return 0, false, fmt.Errorf("invalid value: neither int nor percentage")
+	return 0, false, fmt.Errorf("invalid type: neither int nor percentage")
 }

test/e2e/deployment.go

@@ -80,6 +80,9 @@ var _ = framework.KubeDescribe("Deployment", func() {
 	It("deployment should label adopted RSs and pods", func() {
 		testDeploymentLabelAdopted(f)
 	})
+	It("paused deployment should be able to scale", func() {
+		testScalePausedDeployment(f)
+	})
 })
 
 func newRS(rsName string, replicas int32, rsPodLabels map[string]string, imageName string, image string) *extensions.ReplicaSet {
@@ -569,6 +572,8 @@ func testPausedDeployment(f *framework.Framework) {
 	podLabels := map[string]string{"name": nginxImageName}
 	d := newDeployment(deploymentName, 1, podLabels, nginxImageName, nginxImage, extensions.RollingUpdateDeploymentStrategyType, nil)
 	d.Spec.Paused = true
+	tgps := int64(20)
+	d.Spec.Template.Spec.TerminationGracePeriodSeconds = &tgps
 	framework.Logf("Creating paused deployment %s", deploymentName)
 	_, err := c.Extensions().Deployments(ns).Create(d)
 	Expect(err).NotTo(HaveOccurred())
@@ -622,21 +627,34 @@ func testPausedDeployment(f *framework.Framework) {
 	err = framework.WaitForObservedDeployment(c, ns, deploymentName, deployment.Generation)
 	Expect(err).NotTo(HaveOccurred())
 
-	newRS, err := deploymentutil.GetNewReplicaSet(deployment, c)
+	// Update the deployment template - the new replicaset should stay the same
+	framework.Logf("Updating paused deployment %q", deploymentName)
+	newTGPS := int64(40)
+	deployment, err = framework.UpdateDeploymentWithRetries(c, ns, d.Name, func(update *extensions.Deployment) {
+		update.Spec.Template.Spec.TerminationGracePeriodSeconds = &newTGPS
+	})
 	Expect(err).NotTo(HaveOccurred())
-	Expect(framework.DeleteReplicaSet(unversionedClient, ns, newRS.Name)).NotTo(HaveOccurred())
 
-	deployment, err = c.Extensions().Deployments(ns).Get(deploymentName)
+	err = framework.WaitForObservedDeployment(c, ns, deploymentName, deployment.Generation)
 	Expect(err).NotTo(HaveOccurred())
 
-	if !deployment.Spec.Paused {
-		err = fmt.Errorf("deployment %q should be paused", deployment.Name)
+	framework.Logf("Looking for new replicaset for paused deployment %q (there should be none)", deploymentName)
+	newRS, err := deploymentutil.GetNewReplicaSet(deployment, c)
+	Expect(err).NotTo(HaveOccurred())
+	if newRS != nil {
+		err = fmt.Errorf("No replica set should match the deployment template but there is %q", newRS.Name)
 		Expect(err).NotTo(HaveOccurred())
 	}
-	shouldBeNil, err := deploymentutil.GetNewReplicaSet(deployment, c)
+
+	_, allOldRs, err := deploymentutil.GetOldReplicaSets(deployment, c)
 	Expect(err).NotTo(HaveOccurred())
-	if shouldBeNil != nil {
-		err = fmt.Errorf("deployment %q shouldn't have a replica set but there is %q", deployment.Name, shouldBeNil.Name)
+	if len(allOldRs) != 1 {
+		err = fmt.Errorf("expected an old replica set")
+		Expect(err).NotTo(HaveOccurred())
+	}
+	framework.Logf("Comparing deployment diff with old replica set %q", allOldRs[0].Name)
+	if *allOldRs[0].Spec.Template.Spec.TerminationGracePeriodSeconds == newTGPS {
+		err = fmt.Errorf("TerminationGracePeriodSeconds on the replica set should be %d but is %d", tgps, newTGPS)
 		Expect(err).NotTo(HaveOccurred())
 	}
 }
@@ -944,3 +962,54 @@ func testDeploymentLabelAdopted(f *framework.Framework) {
 	Expect(err).NotTo(HaveOccurred())
 	Expect(int32(len(pods.Items))).Should(Equal(replicas))
 }
+
+func testScalePausedDeployment(f *framework.Framework) {
+	ns := f.Namespace.Name
+	c := adapter.FromUnversionedClient(f.Client)
+
+	podLabels := map[string]string{"name": nginxImageName}
+	replicas := int32(3)
+
+	// Create a nginx deployment.
+	deploymentName := "nginx-deployment"
+	d := newDeployment(deploymentName, replicas, podLabels, nginxImageName, nginxImage, extensions.RollingUpdateDeploymentStrategyType, nil)
+	framework.Logf("Creating deployment %q", deploymentName)
+	_, err := c.Extensions().Deployments(ns).Create(d)
+	Expect(err).NotTo(HaveOccurred())
+	defer stopDeployment(c, f.Client, ns, deploymentName)
+
+	// Check that deployment is created fine.
+	deployment, err := c.Extensions().Deployments(ns).Get(deploymentName)
+	Expect(err).NotTo(HaveOccurred())
+
+	err = framework.WaitForObservedDeployment(c, ns, deploymentName, deployment.Generation)
+	Expect(err).NotTo(HaveOccurred())
+
+	rs, err := deploymentutil.GetNewReplicaSet(deployment, c)
+	Expect(err).NotTo(HaveOccurred())
+
+	// Pause the deployment and try to scale it.
+	deployment, err = framework.UpdateDeploymentWithRetries(c, ns, d.Name, func(update *extensions.Deployment) {
+		update.Spec.Paused = true
+	})
+	Expect(err).NotTo(HaveOccurred())
+
+	// Scale the paused deployment.
+	framework.Logf("Scaling up the paused deployment %q", deploymentName)
+	newReplicas := int32(5)
+	deployment, err = framework.UpdateDeploymentWithRetries(c, ns, deployment.Name, func(update *extensions.Deployment) {
+		update.Spec.Replicas = newReplicas
+	})
+	Expect(err).NotTo(HaveOccurred())
+
+	err = framework.WaitForObservedDeployment(c, ns, deploymentName, deployment.Generation)
+	Expect(err).NotTo(HaveOccurred())
+
+	rs, err = deploymentutil.GetNewReplicaSet(deployment, c)
+	Expect(err).NotTo(HaveOccurred())
+
+	if rs.Spec.Replicas != newReplicas {
+		err = fmt.Errorf("Expected %d replicas for the new replica set, got %d", newReplicas, rs.Spec.Replicas)
+		Expect(err).NotTo(HaveOccurred())
+	}
+}