feat: add goroutine watcher (#16)

* [FEED-8337] feat: add goroutine watcher

* lint

* fix: ci lint

* chore: wrong comment

* feat: handle error

* chore: new line

* feat: add benchmark test for async

* apply reviews

* default value

* macos 11 deprecated on github action

.github/workflows/test.yml

@@ -30,7 +30,7 @@ jobs:
   test-on-macos:
     strategy:
       matrix:
-        os-version: [ 11, 12 ]
+        os-version: [ 12, 13 ]
         go-version: [ 1.16, 1.17, 1.18, 1.19 ]
     runs-on: macos-${{ matrix.os-version }}
     steps:

autopprof.go

@@ -7,6 +7,7 @@ import (
 	"bytes"
 	"context"
 	"fmt"
+	"github.com/daangn/autopprof/queryer"
 	"log"
 	"time"
 
@@ -34,13 +35,22 @@ type autoPprof struct {
 	// Default: 0.75. (mean 75%)
 	memThreshold float64
 
+	// goroutineThreshold is the goroutine count threshold to trigger profile.
+	// If the goroutine count is over the threshold, the autopprof will
+	//  report the goroutine profile.
+	// Default: 50000.
+	goroutineThreshold int
+
 	// minConsecutiveOverThreshold is the minimum consecutive
 	// number of over a threshold for reporting profile again.
 	// Default: 12.
 	minConsecutiveOverThreshold int
 
-	// queryer is used to query the quota and the cgroup stat.
-	queryer queryer
+	// cgroupQueryer is used to query the quota and the cgroup stat.
+	cgroupQueryer queryer.CgroupsQueryer
+
+	// runtimeQueryer is used to query the runtime stat.
+	runtimeQueryer queryer.RuntimeQueryer
 
 	// profiler is used to profile the cpu and the heap memory.
 	profiler profiler
@@ -53,8 +63,9 @@ type autoPprof struct {
 	reportBoth bool
 
 	// Flags to disable the profiling.
-	disableCPUProf bool
-	disableMemProf bool
+	disableCPUProf       bool
+	disableMemProf       bool
+	disableGoroutineProf bool
 
 	// stopC is the signal channel to stop the watch processes.
 	stopC chan struct{}
@@ -65,7 +76,12 @@ var globalAp *autoPprof
 
 // Start configures and runs the autopprof process.
 func Start(opt Option) error {
-	qryer, err := newQueryer()
+	cgroupQryer, err := queryer.NewCgroupQueryer()
+	if err != nil {
+		return err
+	}
+
+	runtimeQryer, err := queryer.NewRuntimeQueryer()
 	if err != nil {
 		return err
 	}
@@ -78,8 +94,10 @@ func Start(opt Option) error {
 		watchInterval:               defaultWatchInterval,
 		cpuThreshold:                defaultCPUThreshold,
 		memThreshold:                defaultMemThreshold,
+		goroutineThreshold:          defaultGoroutineThreshold,
 		minConsecutiveOverThreshold: defaultMinConsecutiveOverThreshold,
-		queryer:                     qryer,
+		cgroupQueryer:               cgroupQryer,
+		runtimeQueryer:              runtimeQryer,
 		profiler:                    profr,
 		reporter:                    opt.Reporter,
 		reportBoth:                  opt.ReportBoth,
@@ -93,6 +111,9 @@ func Start(opt Option) error {
 	if opt.MemThreshold != 0 {
 		ap.memThreshold = opt.MemThreshold
 	}
+	if opt.GoroutineThreshold != 0 {
+		ap.goroutineThreshold = opt.GoroutineThreshold
+	}
 	if !ap.disableCPUProf {
 		if err := ap.loadCPUQuota(); err != nil {
 			return err
@@ -112,7 +133,7 @@ func Stop() {
 }
 
 func (ap *autoPprof) loadCPUQuota() error {
-	err := ap.queryer.setCPUQuota()
+	err := ap.cgroupQueryer.SetCPUQuota()
 	if err == nil {
 		return nil
 	}
@@ -134,6 +155,7 @@ func (ap *autoPprof) loadCPUQuota() error {
 func (ap *autoPprof) watch() {
 	go ap.watchCPUUsage()
 	go ap.watchMemUsage()
+	go ap.watchGoroutineCount()
 	<-ap.stopC
 }
 
@@ -149,7 +171,7 @@ func (ap *autoPprof) watchCPUUsage() {
 	for {
 		select {
 		case <-ticker.C:
-			usage, err := ap.queryer.cpuUsage()
+			usage, err := ap.cgroupQueryer.CPUUsage()
 			if err != nil {
 				log.Println(err)
 				return
@@ -170,7 +192,7 @@ func (ap *autoPprof) watchCPUUsage() {
 					))
 				}
 				if ap.reportBoth && !ap.disableMemProf {
-					memUsage, err := ap.queryer.memUsage()
+					memUsage, err := ap.cgroupQueryer.MemUsage()
 					if err != nil {
 						log.Println(err)
 						return
@@ -226,7 +248,7 @@ func (ap *autoPprof) watchMemUsage() {
 	for {
 		select {
 		case <-ticker.C:
-			usage, err := ap.queryer.memUsage()
+			usage, err := ap.cgroupQueryer.MemUsage()
 			if err != nil {
 				log.Println(err)
 				return
@@ -247,7 +269,7 @@ func (ap *autoPprof) watchMemUsage() {
 					))
 				}
 				if ap.reportBoth && !ap.disableCPUProf {
-					cpuUsage, err := ap.queryer.cpuUsage()
+					cpuUsage, err := ap.cgroupQueryer.CPUUsage()
 					if err != nil {
 						log.Println(err)
 						return
@@ -291,6 +313,68 @@ func (ap *autoPprof) reportHeapProfile(memUsage float64) error {
 	return nil
 }
 
+func (ap *autoPprof) watchGoroutineCount() {
+	if ap.disableGoroutineProf {
+		return
+	}
+
+	ticker := time.NewTicker(ap.watchInterval)
+	defer ticker.Stop()
+
+	var consecutiveOverThresholdCnt int
+	for {
+		select {
+		case <-ticker.C:
+			count := ap.runtimeQueryer.GoroutineCount()
+
+			if count < ap.goroutineThreshold {
+				// Reset the count if the goroutine count goes under the threshold.
+				consecutiveOverThresholdCnt = 0
+				continue
+			}
+
+			// If goroutine count remains high for a short period of time, no
+			//  duplicate reports are sent.
+			// This is to prevent the autopprof from sending too many reports.
+			if consecutiveOverThresholdCnt == 0 {
+				if err := ap.reportGoroutineProfile(count); err != nil {
+					log.Println(fmt.Errorf(
+						"autopprof: failed to report the goroutine profile: %w", err,
+					))
+				}
+			}
+
+			consecutiveOverThresholdCnt++
+			if consecutiveOverThresholdCnt >= ap.minConsecutiveOverThreshold {
+				// Reset the count and ready to report the goroutine profile again.
+				consecutiveOverThresholdCnt = 0
+			}
+		case <-ap.stopC:
+			return
+		}
+	}
+}
+
+func (ap *autoPprof) reportGoroutineProfile(goroutineCount int) error {
+	b, err := ap.profiler.profileGoroutine()
+	if err != nil {
+		return fmt.Errorf("autopprof: failed to profile the goroutine: %w", err)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), reportTimeout)
+	defer cancel()
+
+	gi := report.GoroutineInfo{
+		ThresholdCount: ap.goroutineThreshold,
+		Count:          goroutineCount,
+	}
+	bReader := bytes.NewReader(b)
+	if err := ap.reporter.ReportGoroutineProfile(ctx, bReader, gi); err != nil {
+		return err
+	}
+	return nil
+}
+
 func (ap *autoPprof) stop() {
 	close(ap.stopC)
 }