change kubelet probe metrics to counter type

pkg/kubelet/prober/prober_manager.go

@@ -32,12 +32,29 @@ import (
 	"k8s.io/kubernetes/pkg/kubelet/util/format"
 )
 
-// ProberResults stores the results of a probe as prometheus metrics.
-var ProberResults = prometheus.NewGaugeVec(
+// ProberResults stores the cumulative number of a probe by result as prometheus metrics.
+var ProberResults = prometheus.NewCounterVec(
+	prometheus.CounterOpts{
+		Subsystem: "prober",
+		Name:      "probe_total",
+		Help:      "Cumulative number of a liveness or readiness probe for a container by result.",
+	},
+	[]string{"probe_type",
+		"result",
+		"container",
+		"pod",
+		"namespace",
+		"pod_uid"},
+)
+
+// DeprecatedProberResults stores the results of a probe as prometheus metrics.
+// This metrics is deprecated, will be removed in a future release.
+// Please convert to the metrics of counter type above.
+var DeprecatedProberResults = prometheus.NewGaugeVec(
 	prometheus.GaugeOpts{
 		Subsystem: "prober",
 		Name:      "probe_result",
-		Help:      "The result of a liveness or readiness probe for a container.",
+		Help:      "(Deprecated) The result of a liveness or readiness probe for a container.",
 	},
 	[]string{"probe_type",
 		"container_name",
@@ -130,6 +147,10 @@ type probeType int
 const (
 	liveness probeType = iota
 	readiness
+
+	probeResultSuccessful string = "successful"
+	probeResultFailed     string = "failed"
+	probeResultUnknown    string = "unknown"
 )
 
 // For debugging.

pkg/kubelet/prober/worker.go

@@ -69,7 +69,10 @@ type worker struct {
 
 	// proberResultsMetricLabels holds the labels attached to this worker
 	// for the ProberResults metric.
-	proberResultsMetricLabels prometheus.Labels
+	proberResultsMetricLabels           prometheus.Labels
+	proberResultsSuccessfulMetricLabels prometheus.Labels
+	proberResultsFailedMetricLabels     prometheus.Labels
+	proberResultsUnknownMetricLabels    prometheus.Labels
 }
 
 // Creates and starts a new probe worker.
@@ -98,16 +101,27 @@ func newWorker(
 		w.initialValue = results.Success
 	}
 
-	w.proberResultsMetricLabels = prometheus.Labels{
-		"probe_type":     w.probeType.String(),
-		"container_name": w.container.Name,
-		"container":      w.container.Name,
-		"pod_name":       w.pod.Name,
-		"pod":            w.pod.Name,
-		"namespace":      w.pod.Namespace,
-		"pod_uid":        string(w.pod.UID),
+	basicMetricLabels := prometheus.Labels{
+		"probe_type": w.probeType.String(),
+		"container":  w.container.Name,
+		"pod":        w.pod.Name,
+		"namespace":  w.pod.Namespace,
+		"pod_uid":    string(w.pod.UID),
 	}
 
+	w.proberResultsMetricLabels = deepCopyPrometheusLabels(basicMetricLabels)
+	w.proberResultsMetricLabels["container_name"] = w.container.Name
+	w.proberResultsMetricLabels["pod_name"] = w.pod.Name
+
+	w.proberResultsSuccessfulMetricLabels = deepCopyPrometheusLabels(basicMetricLabels)
+	w.proberResultsSuccessfulMetricLabels["result"] = probeResultSuccessful
+
+	w.proberResultsFailedMetricLabels = deepCopyPrometheusLabels(basicMetricLabels)
+	w.proberResultsFailedMetricLabels["result"] = probeResultFailed
+
+	w.proberResultsUnknownMetricLabels = deepCopyPrometheusLabels(basicMetricLabels)
+	w.proberResultsUnknownMetricLabels["result"] = probeResultUnknown
+
 	return w
 }
 
@@ -129,7 +143,10 @@ func (w *worker) run() {
 		}
 
 		w.probeManager.removeWorker(w.pod.UID, w.container.Name, w.probeType)
-		ProberResults.Delete(w.proberResultsMetricLabels)
+		ProberResults.Delete(w.proberResultsSuccessfulMetricLabels)
+		ProberResults.Delete(w.proberResultsFailedMetricLabels)
+		ProberResults.Delete(w.proberResultsUnknownMetricLabels)
+		DeprecatedProberResults.Delete(w.proberResultsMetricLabels)
 	}()
 
 probeLoop:
@@ -220,6 +237,15 @@ func (w *worker) doProbe() (keepGoing bool) {
 		return true
 	}
 
+	switch result {
+	case results.Success:
+		ProberResults.With(w.proberResultsSuccessfulMetricLabels).Inc()
+	case results.Failure:
+		ProberResults.With(w.proberResultsFailedMetricLabels).Inc()
+	default:
+		ProberResults.With(w.proberResultsUnknownMetricLabels).Inc()
+	}
+
 	if w.lastResult == result {
 		w.resultRun++
 	} else {
@@ -234,7 +260,7 @@ func (w *worker) doProbe() (keepGoing bool) {
 	}
 
 	w.resultsManager.Set(w.containerID, result, w.pod)
-	ProberResults.With(w.proberResultsMetricLabels).Set(result.ToPrometheusType())
+	DeprecatedProberResults.With(w.proberResultsMetricLabels).Set(result.ToPrometheusType())
 
 	if w.probeType == liveness && result == results.Failure {
 		// The container fails a liveness check, it will need to be restarted.
@@ -247,3 +273,11 @@ func (w *worker) doProbe() (keepGoing bool) {
 
 	return true
 }
+
+func deepCopyPrometheusLabels(m prometheus.Labels) prometheus.Labels {
+	ret := make(prometheus.Labels, len(m))
+	for k, v := range m {
+		ret[k] = v
+	}
+	return ret
+}

pkg/kubelet/server/server.go

@@ -321,6 +321,7 @@ func (s *Server) InstallDefaultHandlers() {
 	// prober metrics are exposed under a different endpoint
 	p := prometheus.NewRegistry()
 	p.MustRegister(prober.ProberResults)
+	p.MustRegister(prober.DeprecatedProberResults)
 	s.restfulCont.Handle(proberMetricsPath,
 		promhttp.HandlerFor(p, promhttp.HandlerOpts{ErrorHandling: promhttp.ContinueOnError}),
 	)