Remove ManagedPod,ManagedContainer metrics

This replaces the generic ManagedPod and ManagedContainer kubelet
metrics with a gauge to track only ephemeral container usage.

pkg/kubelet/metrics/metrics.go

@@ -84,14 +84,15 @@ const (
 	RunPodSandboxDurationKey = "run_podsandbox_duration_seconds"
 	RunPodSandboxErrorsKey   = "run_podsandbox_errors_total"
 
-	// Metrics to keep track of objects under management
+	// Metrics to keep track of total number of Pods and Containers started
-	ManagedPodsKey                  = "managed_pods"
-	ManagedContainersKey            = "managed_containers"
 	StartedPodsTotalKey             = "started_pods_total"
 	StartedPodsErrorsTotalKey       = "started_pods_errors_total"
 	StartedContainersTotalKey       = "started_containers_total"
 	StartedContainersErrorsTotalKey = "started_containers_errors_total"
 
+	// Metrics to track ephemeral container usage by this kubelet
+	ManagedEphemeralContainersKey = "managed_ephemeral_containers"
+
 	// Values used in metric labels
 	Container          = "container"
 	InitContainer      = "init_container"
@@ -483,25 +484,15 @@ var (
 		},
 		[]string{"container_type", "code"},
 	)
-	// ManagedPods is a gauge that tracks how many pods are managed by this kubelet
+	// ManagedEphemeralContainers is a gauge that indicates how many ephemeral containers are managed by this kubelet.
-	ManagedPods = metrics.NewGauge(
+	ManagedEphemeralContainers = metrics.NewGauge(
 		&metrics.GaugeOpts{
 			Subsystem:      KubeletSubsystem,
-			Name:           ManagedPodsKey,
+			Name:           ManagedEphemeralContainersKey,
-			Help:           "Number of pods managed by this kubelet",
+			Help:           "Current number of ephemeral containers in pods managed by this kubelet. Ephemeral containers will be ignored if disabled by the EphemeralContainers feature gate, and this number will be 0.",
 			StabilityLevel: metrics.ALPHA,
 		},
 	)
-	// ManagedContainers is a gauge that tracks how many containers are managed by this kubelet
-	ManagedContainers = metrics.NewGaugeVec(
-		&metrics.GaugeOpts{
-			Subsystem:      KubeletSubsystem,
-			Name:           ManagedContainersKey,
-			Help:           "Number of containers managed by this kubelet",
-			StabilityLevel: metrics.ALPHA,
-		},
-		[]string{"container_type"},
-	)
 )
 
 var registerMetrics sync.Once
@@ -530,8 +521,7 @@ func Register(collectors ...metrics.StableCollector) {
 		legacyregistry.MustRegister(DevicePluginAllocationDuration)
 		legacyregistry.MustRegister(RunningContainerCount)
 		legacyregistry.MustRegister(RunningPodCount)
-		legacyregistry.MustRegister(ManagedPods)
+		legacyregistry.MustRegister(ManagedEphemeralContainers)
-		legacyregistry.MustRegister(ManagedContainers)
 		legacyregistry.MustRegister(StartedPodsTotal)
 		legacyregistry.MustRegister(StartedPodsErrorsTotal)
 		legacyregistry.MustRegister(StartedContainersTotal)

pkg/kubelet/pod/pod_manager.go

@@ -162,42 +162,22 @@ func isPodInTerminatedState(pod *v1.Pod) bool {
 	return pod.Status.Phase == v1.PodFailed || pod.Status.Phase == v1.PodSucceeded
 }
 
-// updateMetrics updates the gauge metrics that track how many pods and containers this kubelet manages.
+// updateMetrics updates the metrics surfaced by the pod manager.
-// oldPod or newPod may be nil to signify creation or deletion, respectively.
+// oldPod or newPod may be nil to signify creation or deletion.
 func updateMetrics(oldPod, newPod *v1.Pod) {
-	var numC, numIC, numEC int
+	if !utilfeature.DefaultFeatureGate.Enabled(features.EphemeralContainers) {
-	countEC := utilfeature.DefaultFeatureGate.Enabled(features.EphemeralContainers)
+		return
+	}
 
+	var numEC int
 	if oldPod != nil {
-		if newPod == nil {
+		numEC -= len(oldPod.Spec.EphemeralContainers)
-			metrics.ManagedPods.Dec()
-		}
-		numC -= len(oldPod.Spec.Containers)
-		numIC -= len(oldPod.Spec.InitContainers)
-		if countEC {
-			numEC -= len(oldPod.Spec.EphemeralContainers)
-		}
 	}
-
 	if newPod != nil {
-		if oldPod == nil {
+		numEC += len(newPod.Spec.EphemeralContainers)
-			metrics.ManagedPods.Inc()
-		}
-		numC += len(newPod.Spec.Containers)
-		numIC += len(newPod.Spec.InitContainers)
-		if countEC {
-			numEC += len(newPod.Spec.EphemeralContainers)
-		}
 	}
-
+	if numEC != 0 {
-	if numC != 0 {
+		metrics.ManagedEphemeralContainers.Add(float64(numEC))
-		metrics.ManagedContainers.WithLabelValues(metrics.Container).Add(float64(numC))
-	}
-	if numIC != 0 {
-		metrics.ManagedContainers.WithLabelValues(metrics.InitContainer).Add(float64(numIC))
-	}
-	if countEC && numEC != 0 {
-		metrics.ManagedContainers.WithLabelValues(metrics.EphemeralContainer).Add(float64(numEC))
 	}
 }