add metrics for golang goroutineNum, gcNum and gcPauseTime

Author: jianqingdu

README.md

@@ -3,7 +3,7 @@ sentry sdk for sending metrics to sentry_agent or sentry_server in golang
 
 # Install 
 ```
-https://github.com/sentrycloud/sentry-sdk-go
+go get https://github.com/sentrycloud/sentry-sdk-go
 ```
 
 # Usage

gcinfo.go

@@ -0,0 +1,46 @@
+package sentry
+
+import (
+	"runtime"
+	"runtime/debug"
+	"time"
+)
+
+const GcInterval = 10
+
+var (
+	goNumCollector   = GetCollector("sentry_go_num", nil, Sum, GcInterval)
+	gcNumCollector   = GetCollector("sentry_gc_num", nil, Sum, GcInterval)
+	gcPauseCollector = GetCollector("sentry_gc_pause", nil, Sum, GcInterval)
+
+	lastGCNum   int64         = 0
+	lastGCPause time.Duration = 0
+)
+
+func startCollectGC() {
+	t := time.NewTicker(GcInterval * time.Second)
+
+	for {
+		select {
+		case <-t.C:
+			collectGC()
+		}
+	}
+}
+
+func collectGC() {
+	goNum := runtime.NumGoroutine()
+	goNumCollector.Put(float64(goNum))
+
+	stats := &debug.GCStats{}
+	debug.ReadGCStats(stats)
+
+	gcNum := stats.NumGC - lastGCNum
+	pauseTime := stats.PauseTotal - lastGCPause
+
+	gcNumCollector.Put(float64(gcNum))
+	gcPauseCollector.Put(float64(pauseTime.Milliseconds()))
+
+	lastGCNum = stats.NumGC
+	lastGCPause = stats.PauseTotal
+}

init.go

@@ -4,4 +4,5 @@ func init() {
 	dataChan = make(chan DataPoint, DataChanSize)
 
 	go collect()
+	go startCollectGC()
 }

sentry_test.go

@@ -24,7 +24,7 @@ func aggregatorToString(aggregator CollectorType) string {
 }
 
 func testCollector(aggregator CollectorType, value float64) {
-	metric := "testApp_http_qps"
+	metric := "myapp_http_qps"
 	tags := map[string]string{
 		"from":       "iOS",
 		"aggregator": aggregatorToString(aggregator),
@@ -61,3 +61,8 @@ func TestAllCollectorsInGoroutine(t *testing.T) {
 	go testInGoroutine(&wg, Min)
 	wg.Wait()
 }
+
+func TestGcCollector(t *testing.T) {
+	SetReportURL("http://127.0.0.1:51001/server/api/putMetrics")
+	startCollectGC()
+}