⚠️ Remove duplicate QueueLength metric

The QueueLength metric is now a duplicate of the workqueue "depth"
metric, so it's no longer needed.

pkg/internal/controller/controller.go

@@ -243,6 +243,5 @@ func (c *Controller) InjectFunc(f inject.Func) error {
 
 // updateMetrics updates prometheus metrics within the controller
 func (c *Controller) updateMetrics(reconcileTime time.Duration) {
-	ctrlmetrics.QueueLength.WithLabelValues(c.Name).Set(float64(c.Queue.Len()))
 	ctrlmetrics.ReconcileTime.WithLabelValues(c.Name).Observe(reconcileTime.Seconds())
 }

pkg/internal/controller/controller_test.go

@@ -410,16 +410,7 @@ var _ = Describe("controller", func() {
 
 		Context("should update prometheus metrics", func() {
 			It("should requeue a Request if there is an error and continue processing items", func(done Done) {
-				var queueLength, reconcileErrs dto.Metric
-				ctrlmetrics.QueueLength.Reset()
-				Expect(func() error {
-					ctrlmetrics.QueueLength.WithLabelValues(ctrl.Name).Write(&queueLength)
-					if queueLength.GetGauge().GetValue() != 0.0 {
-						return fmt.Errorf("metrics not reset")
-					}
-					return nil
-				}()).Should(Succeed())
-
+				var reconcileErrs dto.Metric
 				ctrlmetrics.ReconcileErrors.Reset()
 				Expect(func() error {
 					ctrlmetrics.ReconcileErrors.WithLabelValues(ctrl.Name).Write(&reconcileErrs)
@@ -441,13 +432,6 @@ var _ = Describe("controller", func() {
 
 				By("Invoking Reconciler which will give an error")
 				Expect(<-reconciled).To(Equal(request))
-				Eventually(func() error {
-					ctrlmetrics.QueueLength.WithLabelValues(ctrl.Name).Write(&queueLength)
-					if queueLength.GetGauge().GetValue() != 1.0 {
-						return fmt.Errorf("metrics not updated")
-					}
-					return nil
-				}, 2.0).Should(Succeed())
 				Eventually(func() error {
 					ctrlmetrics.ReconcileErrors.WithLabelValues(ctrl.Name).Write(&reconcileErrs)
 					if reconcileErrs.GetCounter().GetValue() != 1.0 {

pkg/internal/controller/metrics/metrics.go

@@ -22,13 +22,6 @@ import (
 )
 
 var (
-	// QueueLength is a prometheus metric which counts the current reconcile
-	// queue length per controller
-	QueueLength = prometheus.NewGaugeVec(prometheus.GaugeOpts{
-		Name: "controller_runtime_reconcile_queue_length",
-		Help: "Length of reconcile queue per controller",
-	}, []string{"controller"})
-
 	// ReconcileErrors is a prometheus counter metrics which holds the total
 	// number of errors from the Reconciler
 	ReconcileErrors = prometheus.NewCounterVec(prometheus.CounterOpts{

pkg/metrics/client_go_adapter.go

@@ -104,6 +104,10 @@ var (
 		Name:      "last_resource_version",
 		Help:      "Last resource version seen for the reflectors",
 	}, []string{"name"})
+
+	// workqueue metrics
+
+	workQueueSubsystem = "workqueue"
 )
 
 func init() {
@@ -206,6 +210,8 @@ func (reflectorMetricsProvider) NewLastResourceVersionMetric(name string) reflec
 // Workqueue metrics (method #3 for client-go metrics),
 // copied (more-or-less directly) from k8s.io/kubernetes setup code
 // (which isn't anywhere in an easily-importable place).
+// TODO(directxman12): stop "cheating" and calling histograms summaries when we pull in the latest deps
+// TODO(directxman12): add in unfinished_work and longest_running_processor when we pull in the latest deps
 
 // NB(directxman12): these are changed to MustRegister from Register.  It's not clear why they weren't
 // MustRegister in the first place, except maybe to not bring down the controller if the metrics fail
@@ -215,50 +221,57 @@ type workqueueMetricsProvider struct{}
 
 func (workqueueMetricsProvider) NewDepthMetric(name string) workqueuemetrics.GaugeMetric {
 	depth := prometheus.NewGauge(prometheus.GaugeOpts{
-		Subsystem: name,
-		Name:      "depth",
-		Help:      "Current depth of workqueue: " + name,
+		Subsystem:   workQueueSubsystem,
+		Name:        "depth",
+		Help:        "Current depth of workqueue",
+		ConstLabels: prometheus.Labels{"name": name},
 	})
-	Registry.MustRegister(depth)
+	prometheus.MustRegister(depth)
 	return depth
 }
 
 func (workqueueMetricsProvider) NewAddsMetric(name string) workqueuemetrics.CounterMetric {
 	adds := prometheus.NewCounter(prometheus.CounterOpts{
-		Subsystem: name,
-		Name:      "adds",
-		Help:      "Total number of adds handled by workqueue: " + name,
+		Subsystem:   workQueueSubsystem,
+		Name:        "adds_total",
+		Help:        "Total number of adds handled by workqueue",
+		ConstLabels: prometheus.Labels{"name": name},
 	})
-	Registry.MustRegister(adds)
+	prometheus.MustRegister(adds)
 	return adds
 }
 
 func (workqueueMetricsProvider) NewLatencyMetric(name string) workqueuemetrics.SummaryMetric {
-	latency := prometheus.NewSummary(prometheus.SummaryOpts{
-		Subsystem: name,
-		Name:      "queue_latency",
-		Help:      "How long an item stays in workqueue" + name + " before being requested.",
+	latency := prometheus.NewHistogram(prometheus.HistogramOpts{
+		Subsystem:   workQueueSubsystem,
+		Name:        "queue_latency_seconds",
+		Help:        "How long in seconds an item stays in workqueue before being requested.",
+		ConstLabels: prometheus.Labels{"name": name},
+		Buckets:     prometheus.ExponentialBuckets(10e-9, 10, 10),
 	})
-	Registry.MustRegister(latency)
+	prometheus.MustRegister(latency)
 	return latency
 }
 
 func (workqueueMetricsProvider) NewWorkDurationMetric(name string) workqueuemetrics.SummaryMetric {
-	workDuration := prometheus.NewSummary(prometheus.SummaryOpts{
-		Subsystem: name,
-		Name:      "work_duration",
-		Help:      "How long processing an item from workqueue" + name + " takes.",
+	workDuration := prometheus.NewHistogram(prometheus.HistogramOpts{
+		Subsystem:   workQueueSubsystem,
+		Name:        "work_duration_seconds",
+		Help:        "How long in seconds processing an item from workqueue takes.",
+		ConstLabels: prometheus.Labels{"name": name},
+		Buckets:     prometheus.ExponentialBuckets(10e-9, 10, 10),
 	})
-	Registry.MustRegister(workDuration)
+	prometheus.MustRegister(workDuration)
 	return workDuration
 }
 
 func (workqueueMetricsProvider) NewRetriesMetric(name string) workqueuemetrics.CounterMetric {
 	retries := prometheus.NewCounter(prometheus.CounterOpts{
-		Subsystem: name,
-		Name:      "retries",
-		Help:      "Total number of retries handled by workqueue: " + name,
+		Subsystem:   workQueueSubsystem,
+		Name:        "retries_total",
+		Help:        "Total number of retries handled by workqueue",
+		ConstLabels: prometheus.Labels{"name": name},
 	})
-	Registry.MustRegister(retries)
+	prometheus.MustRegister(retries)
 	return retries
 }