PV Controller: PV plugin and mode metrics

pkg/controller/volume/persistentvolume/metrics/BUILD

@@ -6,6 +6,7 @@ go_library(
     importpath = "k8s.io/kubernetes/pkg/controller/volume/persistentvolume/metrics",
     visibility = ["//visibility:public"],
     deps = [
+        "//pkg/volume:go_default_library",
         "//pkg/volume/util:go_default_library",
         "//staging/src/k8s.io/api/core/v1:go_default_library",
         "//staging/src/k8s.io/component-base/metrics:go_default_library",

pkg/controller/volume/persistentvolume/metrics/metrics.go

@@ -23,6 +23,7 @@ import (
 	v1 "k8s.io/api/core/v1"
 	"k8s.io/component-base/metrics"
 	"k8s.io/component-base/metrics/legacyregistry"
+	"k8s.io/kubernetes/pkg/volume"
 	metricutil "k8s.io/kubernetes/pkg/volume/util"
 )
 
@@ -31,6 +32,7 @@ const (
 	pvControllerSubsystem = "pv_collector"
 
 	// Metric names.
+	totalPVKey    = "total_pv_count"
 	boundPVKey    = "bound_pv_count"
 	unboundPVKey  = "unbound_pv_count"
 	boundPVCKey   = "bound_pvc_count"
@@ -39,6 +41,11 @@ const (
 	// Label names.
 	namespaceLabel    = "namespace"
 	storageClassLabel = "storage_class"
+	pluginNameLabel   = "plugin_name"
+	volumeModeLabel   = "volume_mode"
+
+	// String to use when plugin name cannot be determined
+	pluginNameNotAvailable = "N/A"
 )
 
 var registerMetrics sync.Once
@@ -54,15 +61,15 @@ type PVCLister interface {
 }
 
 // Register all metrics for pv controller.
-func Register(pvLister PVLister, pvcLister PVCLister) {
+func Register(pvLister PVLister, pvcLister PVCLister, pluginMgr *volume.VolumePluginMgr) {
 	registerMetrics.Do(func() {
-		legacyregistry.CustomMustRegister(newPVAndPVCCountCollector(pvLister, pvcLister))
+		legacyregistry.CustomMustRegister(newPVAndPVCCountCollector(pvLister, pvcLister, pluginMgr))
 		legacyregistry.MustRegister(volumeOperationErrorsMetric)
 	})
 }
 
-func newPVAndPVCCountCollector(pvLister PVLister, pvcLister PVCLister) *pvAndPVCCountCollector {
+func newPVAndPVCCountCollector(pvLister PVLister, pvcLister PVCLister, pluginMgr *volume.VolumePluginMgr) *pvAndPVCCountCollector {
-	return &pvAndPVCCountCollector{pvLister: pvLister, pvcLister: pvcLister}
+	return &pvAndPVCCountCollector{pvLister: pvLister, pvcLister: pvcLister, pluginMgr: pluginMgr}
 }
 
 // Custom collector for current pod and container counts.
@@ -73,12 +80,19 @@ type pvAndPVCCountCollector struct {
 	pvLister PVLister
 	// Cache for accessing information about PersistentVolumeClaims.
 	pvcLister PVCLister
+	// Volume plugin manager
+	pluginMgr *volume.VolumePluginMgr
 }
 
 // Check if our collector implements necessary collector interface
 var _ metrics.StableCollector = &pvAndPVCCountCollector{}
 
 var (
+	totalPVCountDesc = metrics.NewDesc(
+		metrics.BuildFQName("", pvControllerSubsystem, totalPVKey),
+		"Gauge measuring total number of persistent volumes",
+		[]string{pluginNameLabel, volumeModeLabel}, nil,
+		metrics.ALPHA, "")
 	boundPVCountDesc = metrics.NewDesc(
 		metrics.BuildFQName("", pvControllerSubsystem, boundPVKey),
 		"Gauge measuring number of persistent volume currently bound",
@@ -110,7 +124,20 @@ var (
 		[]string{"plugin_name", "operation_name"})
 )
 
+// volumeCount counts by PluginName and VolumeMode.
+type volumeCount map[string]map[string]int
+
+func (v volumeCount) add(pluginName string, volumeMode string) {
+	count, ok := v[pluginName]
+	if !ok {
+		count = map[string]int{}
+	}
+	count[volumeMode]++
+	v[pluginName] = count
+}
+
 func (collector *pvAndPVCCountCollector) DescribeWithStability(ch chan<- *metrics.Desc) {
+	ch <- totalPVCountDesc
 	ch <- boundPVCountDesc
 	ch <- unboundPVCountDesc
 	ch <- boundPVCCountDesc
@@ -122,14 +149,26 @@ func (collector *pvAndPVCCountCollector) CollectWithStability(ch chan<- metrics.
 	collector.pvcCollect(ch)
 }
 
+func (collector *pvAndPVCCountCollector) getPVPluginName(pv *v1.PersistentVolume) string {
+	spec := volume.NewSpecFromPersistentVolume(pv, true)
+	fullPluginName := pluginNameNotAvailable
+	if plugin, err := collector.pluginMgr.FindPluginBySpec(spec); err == nil {
+		fullPluginName = metricutil.GetFullQualifiedPluginNameForVolume(plugin.GetPluginName(), spec)
+	}
+	return fullPluginName
+}
+
 func (collector *pvAndPVCCountCollector) pvCollect(ch chan<- metrics.Metric) {
 	boundNumberByStorageClass := make(map[string]int)
 	unboundNumberByStorageClass := make(map[string]int)
+	totalCount := make(volumeCount)
 	for _, pvObj := range collector.pvLister.List() {
 		pv, ok := pvObj.(*v1.PersistentVolume)
 		if !ok {
 			continue
 		}
+		pluginName := collector.getPVPluginName(pv)
+		totalCount.add(pluginName, string(*pv.Spec.VolumeMode))
 		if pv.Status.Phase == v1.VolumeBound {
 			boundNumberByStorageClass[pv.Spec.StorageClassName]++
 		} else {
@@ -150,6 +189,16 @@ func (collector *pvAndPVCCountCollector) pvCollect(ch chan<- metrics.Metric) {
 			float64(number),
 			storageClassName)
 	}
+	for pluginName, volumeModeCount := range totalCount {
+		for volumeMode, number := range volumeModeCount {
+			ch <- metrics.NewLazyConstMetric(
+				totalPVCountDesc,
+				metrics.GaugeValue,
+				float64(number),
+				pluginName,
+				volumeMode)
+		}
+	}
 }
 
 func (collector *pvAndPVCCountCollector) pvcCollect(ch chan<- metrics.Metric) {

pkg/controller/volume/persistentvolume/pv_controller_base.go

@@ -317,7 +317,7 @@ func (ctrl *PersistentVolumeController) Run(stopCh <-chan struct{}) {
 	go wait.Until(ctrl.volumeWorker, time.Second, stopCh)
 	go wait.Until(ctrl.claimWorker, time.Second, stopCh)
 
-	metrics.Register(ctrl.volumes.store, ctrl.claims)
+	metrics.Register(ctrl.volumes.store, ctrl.claims, &ctrl.volumePluginMgr)
 
 	<-stopCh
 }