Merge pull request #16156 from piosz/hpa-test

Improved HPA e2e to test stability of the scale decision

test/e2e/autoscaling_utils.go

@@ -231,6 +231,17 @@ func (rc *ResourceConsumer) WaitForReplicas(desiredReplicas int) {
 	Failf("timeout waiting %v for pods size to be %d", timeout, desiredReplicas)
 }
 
+func (rc *ResourceConsumer) EnsureDesiredReplicas(desiredReplicas int, timeout time.Duration) {
+	for start := time.Now(); time.Since(start) < timeout; time.Sleep(10 * time.Second) {
+		actual := rc.GetReplicas()
+		if desiredReplicas != actual {
+			Failf("Number of replicas has changed: expected %v, got %v", desiredReplicas, actual)
+		}
+		Logf("Number of replicas is as expected")
+	}
+	Logf("Number of replicas was stable over %v", timeout)
+}
+
 func (rc *ResourceConsumer) CleanUp() {
 	By(fmt.Sprintf("Removing consuming RC %s", rc.name))
 	rc.stopCPU <- 0

test/e2e/horizontal_pod_autoscaling.go

@@ -17,6 +17,8 @@ limitations under the License.
 package e2e
 
 import (
+	"time"
+
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/apis/extensions"
 
@@ -24,8 +26,9 @@ import (
 )
 
 const (
-	kind        = "replicationController"
-	subresource = "scale"
+	kind             = "replicationController"
+	subresource      = "scale"
+	stabilityTimeout = 10 * time.Minute
 )
 
 var _ = Describe("Horizontal pod autoscaling", func() {
@@ -38,6 +41,7 @@ var _ = Describe("Horizontal pod autoscaling", func() {
 		defer rc.CleanUp()
 		createCPUHorizontalPodAutoscaler(rc, 20)
 		rc.WaitForReplicas(3)
+		rc.EnsureDesiredReplicas(3, stabilityTimeout)
 		rc.ConsumeCPU(700)
 		rc.WaitForReplicas(5)
 	})
@@ -47,6 +51,7 @@ var _ = Describe("Horizontal pod autoscaling", func() {
 		defer rc.CleanUp()
 		createCPUHorizontalPodAutoscaler(rc, 30)
 		rc.WaitForReplicas(3)
+		rc.EnsureDesiredReplicas(3, stabilityTimeout)
 		rc.ConsumeCPU(100)
 		rc.WaitForReplicas(1)
 	})