Always run OTEL collector and optionally continue running after bench…

…marks (#29)

cmd/apmbench/config.go

@@ -17,19 +17,18 @@ import (
 var cfg struct {
 	Count     uint
 	Benchtime time.Duration
-	Detailed  bool
 	RunRE     *regexp.Regexp
 	// Sorted list of agents count to be used for benchmarking
 	AgentsList          []int
 	CollectorConfigYaml string
+	ServerMode          bool
 }
 
 func init() {
 	cfg.AgentsList = []int{1}
 
 	flag.UintVar(&cfg.Count, "count", 1, "run benchmarks `n` times")
 	flag.DurationVar(&cfg.Benchtime, "benchtime", time.Second, "run each benchmark for duration `d`")
-	flag.BoolVar(&cfg.Detailed, "detailed", false, "Get detailed metrics recorded during benchmark")
 	flag.Func("run", "run only benchmarks matching `regexp`", func(restr string) error {
 		if restr != "" {
 			re, err := regexp.Compile(restr)
@@ -60,4 +59,5 @@ func init() {
 		},
 	)
 	flag.StringVar(&cfg.CollectorConfigYaml, "collector-config-yaml", "", "configuration for otel collector")
+	flag.BoolVar(&cfg.ServerMode, "server-mode", false, "continue running otel collector post benchmark run")
 }

cmd/apmbench/main.go

@@ -9,6 +9,8 @@ import (
 	"errors"
 	"flag"
 	"log"
+	"os"
+	"os/signal"
 	"sync"
 	"testing"
 	"time"
@@ -26,65 +28,61 @@ func main() {
 		log.Fatalf("failed to setup logger: %v", err)
 	}
 
-	extraMetrics := func(*testing.B) error { return nil }
-	resetFunc := func() {}
+	// Create otel collector
+	collectorCfg := otelcollector.DefaultConfig()
 	if cfg.CollectorConfigYaml != "" {
-		logger.Info("starting otel collector...")
-
-		collectorCfg := otelcollector.DefaultConfig()
 		err := collectorCfg.LoadConfigFromYamlFile(cfg.CollectorConfigYaml)
 		if err != nil {
 			logger.Fatal("failed to load collector config", zap.Error(err))
 		}
+	}
+	collector, err := otelcollector.New(collectorCfg, logger)
+	if err != nil {
+		logger.Fatal("failed to create a new collector", zap.Error(err))
+	}
+	logger.Info("loaded collector configuration", zap.Object("config", &collectorCfg))
 
-		collector, err := otelcollector.New(collectorCfg, logger)
-		if err != nil {
-			logger.Fatal("failed to create a new collector", zap.Error(err))
-		}
-		logger.Info("loaded collector configuration", zap.Object("config", &collectorCfg))
-
-		var wg sync.WaitGroup
-		defer wg.Wait()
-		ctx, cancel := context.WithCancel(context.Background())
-		defer cancel()
+	// Start otel collector
+	var wg sync.WaitGroup
+	defer wg.Wait()
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	wg.Add(1)
+	go func(ctx context.Context) {
+		defer wg.Done()
 
-		wg.Add(1)
-		go func(ctx context.Context) {
-			defer wg.Done()
+		logger.Info("starting otel collector...")
+		if err := collector.Run(ctx); err != nil {
+			logger.Fatal("failed to run collector", zap.Error(err))
+		}
+	}(ctx)
 
-			if err := collector.Run(ctx); err != nil {
-				logger.Fatal("failed to run collector", zap.Error(err))
-			}
-		}(ctx)
+	// Wait for otel collector to be ready
+	ctx, cancel = context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+	if err := collector.Wait(ctx); err != nil {
+		logger.Fatal("failed to start collector", zap.Error(err))
+	}
 
-		extraMetrics = func(b *testing.B) error {
-			var errs []error
-			for _, cfg := range collectorCfg.InMemoryStoreConfig {
-				m, err := collector.GetAggregatedMetric(cfg)
-				if err != nil {
-					errs = append(errs, err)
-					continue
-				}
-				b.ReportMetric(m, cfg.Alias)
-			}
-			if len(errs) > 0 {
-				return errors.Join(errs...)
+	// Run benchmarks
+	extraMetrics := func(b *testing.B) error {
+		var errs []error
+		for _, cfg := range collectorCfg.InMemoryStoreConfig {
+			m, err := collector.GetAggregatedMetric(cfg)
+			if err != nil {
+				errs = append(errs, err)
+				continue
 			}
-			return nil
+			b.ReportMetric(m, cfg.Alias)
 		}
-		resetFunc = collector.Reset
-
-		// Wait for otel collector to be ready
-		ctx, cancel = context.WithTimeout(context.Background(), 5*time.Second)
-		defer cancel()
-		if err := collector.Wait(ctx); err != nil {
-			logger.Fatal("failed to start collector", zap.Error(err))
+		if len(errs) > 0 {
+			return errors.Join(errs...)
 		}
+		return nil
 	}
-
 	if err := Run(
 		extraMetrics,
-		resetFunc,
+		collector.Reset,
 		Benchmark1000Transactions,
 		BenchmarkOTLPTraces,
 		BenchmarkAgentAll,
@@ -96,6 +94,13 @@ func main() {
 	); err != nil {
 		logger.Fatal("failed to run benchmarks", zap.Error(err))
 	}
+
+	// If server-mode is enabled then keep the otel collector running
+	if cfg.ServerMode {
+		c := make(chan os.Signal, 1)
+		signal.Notify(c, os.Interrupt)
+		<-c
+	}
 }
 
 func init() {