adding e2e test to ensure it takes less than 10 seconds to query kubelet stats for windows nodes

test/e2e/windows/BUILD

@@ -11,6 +11,7 @@ go_library(
         "gmsa_full.go",
         "gmsa_kubelet.go",
         "hybrid_network.go",
+        "kubelet_stats.go",
         "memory_limits.go",
         "security_context.go",
         "service.go",
@@ -35,6 +36,7 @@ go_library(
         "//staging/src/k8s.io/kubelet/config/v1beta1:go_default_library",
         "//test/e2e/framework:go_default_library",
         "//test/e2e/framework/kubectl:go_default_library",
+        "//test/e2e/framework/kubelet:go_default_library",
         "//test/e2e/framework/metrics:go_default_library",
         "//test/e2e/framework/node:go_default_library",
         "//test/e2e/framework/pod:go_default_library",

test/e2e/windows/kubelet_stats.go

@@ -0,0 +1,157 @@
+/*
+Copyright 2020 The Kubernetes Authors.
+
+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 windows
+
+import (
+	"time"
+
+	v1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/labels"
+	"k8s.io/apimachinery/pkg/util/uuid"
+	"k8s.io/kubernetes/test/e2e/framework"
+	e2ekubelet "k8s.io/kubernetes/test/e2e/framework/kubelet"
+	e2enode "k8s.io/kubernetes/test/e2e/framework/node"
+	e2epod "k8s.io/kubernetes/test/e2e/framework/pod"
+	e2eskipper "k8s.io/kubernetes/test/e2e/framework/skipper"
+	imageutils "k8s.io/kubernetes/test/utils/image"
+
+	"github.com/onsi/ginkgo"
+)
+
+var _ = SIGDescribe("[Feature:Windows] Kubelet-Stats", func() {
+	f := framework.NewDefaultFramework("kubelet-stats-test-windows")
+
+	ginkgo.Describe("Kubelet stats collection for Windows nodes", func() {
+		ginkgo.Context("when running 10 pods", func() {
+			// 10 seconds is the default scrape timeout for metrics-server and kube-prometheus
+			ginkgo.It("should return within 10 seconds", func() {
+
+				ginkgo.By("Selecting a Windows node")
+				targetNode, err := findWindowsNode(f)
+				framework.ExpectNoError(err, "Error finding Windows node")
+				framework.Logf("Using node: %v", targetNode.Name)
+
+				ginkgo.By("Scheduling 10 pods")
+				powershellImage := imageutils.GetConfig(imageutils.BusyBox)
+				pods := newKubeletStatsTestPods(10, powershellImage, targetNode.Name)
+				f.PodClient().CreateBatch(pods)
+
+				ginkgo.By("Waiting up to 3 minutes for pods to be running")
+				timeout := 3 * time.Minute
+				e2epod.WaitForPodsRunningReady(f.ClientSet, f.Namespace.Name, 10, 0, timeout, make(map[string]string))
+
+				ginkgo.By("Getting kubelet stats 5 times and checking average duration")
+				iterations := 5
+				var totalDurationMs int64
+
+				for i := 0; i < iterations; i++ {
+					start := time.Now()
+					nodeStats, err := e2ekubelet.GetStatsSummary(f.ClientSet, targetNode.Name)
+					duration := time.Since(start)
+					totalDurationMs += duration.Milliseconds()
+
+					framework.ExpectNoError(err, "Error getting kubelet stats")
+
+					// Perform some basic sanity checks on retrieved stats for pods in this test's namespace
+					statsChecked := 0
+					for _, podStats := range nodeStats.Pods {
+						if podStats.PodRef.Namespace != f.Namespace.Name {
+							continue
+						}
+						statsChecked = statsChecked + 1
+
+						framework.ExpectEqual(*podStats.CPU.UsageCoreNanoSeconds > 0, true, "Pod stats should not report 0 cpu usage")
+						framework.ExpectEqual(*podStats.Memory.WorkingSetBytes > 0, true, "Pod stats should not report 0 bytes for memory working set ")
+					}
+					framework.ExpectEqual(statsChecked, 10, "Should find stats for 10 pods in kubelet stats")
+
+					time.Sleep(5 * time.Second)
+				}
+
+				avgDurationMs := totalDurationMs / int64(iterations)
+
+				durationMatch := avgDurationMs <= time.Duration(10*time.Second).Milliseconds()
+				framework.Logf("Getting kubelet stats for node %v took an average of %v milliseconds over %v iterations", targetNode.Name, avgDurationMs, iterations)
+				framework.ExpectEqual(durationMatch, true, "Collecting kubelet stats should not take longer than 10 seconds")
+			})
+		})
+	})
+})
+
+// findWindowsNode finds a Windows node that is Ready and Schedulable
+func findWindowsNode(f *framework.Framework) (v1.Node, error) {
+	selector := labels.Set{"kubernetes.io/os": "windows"}.AsSelector()
+	nodeList, err := f.ClientSet.CoreV1().Nodes().List(metav1.ListOptions{LabelSelector: selector.String()})
+
+	if err != nil {
+		return v1.Node{}, err
+	}
+
+	var targetNode v1.Node
+	foundNode := false
+	for _, n := range nodeList.Items {
+		if e2enode.IsNodeReady(&n) && e2enode.IsNodeSchedulable(&n) {
+			targetNode = n
+			foundNode = true
+			break
+		}
+	}
+
+	if foundNode == false {
+		e2eskipper.Skipf("Could not find and ready and schedulable Windows nodes")
+	}
+
+	return targetNode, nil
+}
+
+// newKubeletStatsTestPods creates a list of pods (specification) for test.
+func newKubeletStatsTestPods(numPods int, image imageutils.Config, nodeName string) []*v1.Pod {
+	var pods []*v1.Pod
+
+	for i := 0; i < numPods; i++ {
+		podName := "statscollectiontest-" + string(uuid.NewUUID())
+		pod := v1.Pod{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: podName,
+				Labels: map[string]string{
+					"name":    podName,
+					"testapp": "stats-collection",
+				},
+			},
+			Spec: v1.PodSpec{
+				Containers: []v1.Container{
+					{
+						Image: image.GetE2EImage(),
+						Name:  podName,
+						Command: []string{
+							"powershell.exe",
+							"-Command",
+							"sleep -Seconds 600",
+						},
+					},
+				},
+
+				NodeName: nodeName,
+			},
+		}
+
+		pods = append(pods, &pod)
+	}
+
+	return pods
+}