From 628c0f42fef46b2719cae93a81ae1a8e53ee68fe Mon Sep 17 00:00:00 2001
From: Denis Kirillov <denis@nspcc.ru>
Date: Thu, 25 Aug 2022 09:22:42 +0300
Subject: [PATCH] [#680] Use gauge instead of counter for metrics

Signed-off-by: Denis Kirillov <denis@nspcc.ru>
---
 cmd/s3-gw/app_metrics.go | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/cmd/s3-gw/app_metrics.go b/cmd/s3-gw/app_metrics.go
index 5ca423a..aa58199 100644
--- a/cmd/s3-gw/app_metrics.go
+++ b/cmd/s3-gw/app_metrics.go
@@ -47,9 +47,9 @@ type stateMetrics struct {
 
 type poolMetricsCollector struct {
 	poolStatScraper     StatisticScraper
-	overallErrors       prometheus.Counter
-	overallNodeErrors   *prometheus.CounterVec
-	overallNodeRequests *prometheus.CounterVec
+	overallErrors       prometheus.Gauge
+	overallNodeErrors   *prometheus.GaugeVec
+	overallNodeRequests *prometheus.GaugeVec
 	currentErrors       *prometheus.GaugeVec
 	requestDuration     *prometheus.GaugeVec
 }
@@ -87,8 +87,8 @@ func (m stateMetrics) SetHealth(s int32) {
 }
 
 func newPoolMetricsCollector(scraper StatisticScraper) *poolMetricsCollector {
-	overallErrors := prometheus.NewCounter(
-		prometheus.CounterOpts{
+	overallErrors := prometheus.NewGauge(
+		prometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: poolSubsystem,
 			Name:      "overall_errors",
@@ -96,8 +96,8 @@ func newPoolMetricsCollector(scraper StatisticScraper) *poolMetricsCollector {
 		},
 	)
 
-	overallNodeErrors := prometheus.NewCounterVec(
-		prometheus.CounterOpts{
+	overallNodeErrors := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: poolSubsystem,
 			Name:      "overall_node_errors",
@@ -108,8 +108,8 @@ func newPoolMetricsCollector(scraper StatisticScraper) *poolMetricsCollector {
 		},
 	)
 
-	overallNodeRequests := prometheus.NewCounterVec(
-		prometheus.CounterOpts{
+	overallNodeRequests := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: poolSubsystem,
 			Name:      "overall_node_requests",
@@ -179,18 +179,20 @@ func (m *poolMetricsCollector) register() {
 func (m *poolMetricsCollector) updateStatistic() {
 	stat := m.poolStatScraper.Statistic()
 
+	m.overallNodeErrors.Reset()
+	m.overallNodeRequests.Reset()
 	m.currentErrors.Reset()
 	m.requestDuration.Reset()
 
 	for _, node := range stat.Nodes() {
-		m.overallNodeErrors.WithLabelValues(node.Address()).Add(float64(node.OverallErrors()))
-		m.overallNodeRequests.WithLabelValues(node.Address()).Add(float64(node.Requests()))
+		m.overallNodeErrors.WithLabelValues(node.Address()).Set(float64(node.OverallErrors()))
+		m.overallNodeRequests.WithLabelValues(node.Address()).Set(float64(node.Requests()))
 
 		m.currentErrors.WithLabelValues(node.Address()).Set(float64(node.CurrentErrors()))
 		m.updateRequestsDuration(node)
 	}
 
-	m.overallErrors.Add(float64(stat.OverallErrors()))
+	m.overallErrors.Set(float64(stat.OverallErrors()))
 }
 
 func (m *poolMetricsCollector) updateRequestsDuration(node pool.NodeStatistic) {