set type of mysql_global_status_threads_* to gauge

Signed-off-by: Ali Orouji <ali.orouji@booking.com>

collector/global_status.go

@@ -34,7 +34,7 @@ const (
 )
 
 // Regexp to match various groups of status vars.
-var globalStatusRE = regexp.MustCompile(`^(com|handler|connection_errors|innodb_buffer_pool_pages|innodb_rows|performance_schema)_(.*)$`)
+var globalStatusRE = regexp.MustCompile(`^(com|handler|connection_errors|innodb_buffer_pool_pages|innodb_rows|performance_schema|threads)_(.*)$`)
 
 // Metric descriptors.
 var (
@@ -78,6 +78,11 @@ var (
 		"Total number of MySQL instrumentations that could not be loaded or created due to memory constraints.",
 		[]string{"instrumentation"}, nil,
 	)
+	globalThreadsDesc = prometheus.NewDesc(
+		prometheus.BuildFQName(namespace, globalStatus, "threads"),
+		"MySQL threads in each state.",
+		[]string{"state"}, nil,
+	)
 )
 
 // ScrapeGlobalStatus collects from `SHOW GLOBAL STATUS`.
@@ -168,6 +173,10 @@ func (ScrapeGlobalStatus) Scrape(ctx context.Context, db *sql.DB, ch chan<- prom
 				ch <- prometheus.MustNewConstMetric(
 					globalPerformanceSchemaLostDesc, prometheus.CounterValue, floatVal, match[2],
 				)
+			case "threads":
+				ch <- prometheus.MustNewConstMetric(
+					globalThreadsDesc, prometheus.GaugeValue, floatVal, match[2],
+				)
 			}
 		} else if _, ok := textItems[key]; ok {
 			textItems[key] = string(val)

collector/global_status_test.go

@@ -50,6 +50,10 @@ func TestScrapeGlobalStatus(t *testing.T) {
 		AddRow("Innodb_buffer_pool_pages_made_young", "15").
 		AddRow("Innodb_rows_read", "8").
 		AddRow("Performance_schema_users_lost", "9").
+		AddRow("Threads_cached", "7").
+		AddRow("Threads_connected", "18").
+		AddRow("Threads_created", "25").
+		AddRow("Threads_running", "1").
 		AddRow("Slave_running", "OFF").
 		AddRow("Ssl_version", "").
 		AddRow("Uptime", "10").
@@ -87,6 +91,10 @@ func TestScrapeGlobalStatus(t *testing.T) {
 		{labels: labelMap{"operation": "made_young"}, value: 15, metricType: dto.MetricType_COUNTER},
 		{labels: labelMap{"operation": "read"}, value: 8, metricType: dto.MetricType_COUNTER},
 		{labels: labelMap{"instrumentation": "users_lost"}, value: 9, metricType: dto.MetricType_COUNTER},
+		{labels: labelMap{"state": "cached"}, value: 7, metricType: dto.MetricType_GAUGE},
+		{labels: labelMap{"state": "connected"}, value: 18, metricType: dto.MetricType_GAUGE},
+		{labels: labelMap{"state": "created"}, value: 25, metricType: dto.MetricType_GAUGE},
+		{labels: labelMap{"state": "running"}, value: 1, metricType: dto.MetricType_GAUGE},
 		{labels: labelMap{}, value: 0, metricType: dto.MetricType_UNTYPED},
 		{labels: labelMap{}, value: 10, metricType: dto.MetricType_UNTYPED},
 		{labels: labelMap{}, value: 11, metricType: dto.MetricType_UNTYPED},