profile: add trace

core/commands/profile.go

@@ -85,6 +85,7 @@ However, it could reveal:
 				profile.CollectorCPU,
 				profile.CollectorMutex,
 				profile.CollectorBlock,
+				profile.CollectorTrace,
 			}),
 		cmds.StringOption(profileTimeOption, "The amount of time spent profiling. If this is set to 0, then sampling profiles are skipped.").WithDefault("30s"),
 		cmds.IntOption(mutexProfileFractionOption, "The fraction 1/n of mutex contention events that are reported in the mutex profile.").WithDefault(4),

profile/profile.go

@@ -10,6 +10,7 @@ import (
 	"os"
 	"runtime"
 	"runtime/pprof"
+	"runtime/trace"
 	"sync"
 	"time"
 
@@ -27,6 +28,7 @@ const (
 	CollectorCPU             = "cpu"
 	CollectorMutex           = "mutex"
 	CollectorBlock           = "block"
+	CollectorTrace           = "trace"
 )
 
 var (
@@ -98,6 +100,11 @@ var collectors = map[string]collector{
 		collectFunc: blockProfile,
 		enabledFunc: func(opts Options) bool { return opts.ProfileDuration > 0 && opts.BlockProfileRate > 0 },
 	},
+	CollectorTrace: {
+		outputFile:  "trace",
+		collectFunc: captureTrace,
+		enabledFunc: func(opts Options) bool { return opts.ProfileDuration > 0 },
+	},
 }
 
 type Options struct {
@@ -266,6 +273,15 @@ func profileCPU(ctx context.Context, opts Options, w io.Writer) error {
 	return waitOrCancel(ctx, opts.ProfileDuration)
 }
 
+func captureTrace(ctx context.Context, opts Options, w io.Writer) error {
+	err := trace.Start(w)
+	if err != nil {
+		return err
+	}
+	defer trace.Stop()
+	return waitOrCancel(ctx, opts.ProfileDuration)
+}
+
 func waitOrCancel(ctx context.Context, d time.Duration) error {
 	timer := time.NewTimer(d)
 	defer timer.Stop()

profile/profile_test.go

@@ -22,6 +22,7 @@ func TestProfiler(t *testing.T) {
 		CollectorCPU,
 		CollectorMutex,
 		CollectorBlock,
+		CollectorTrace,
 	}
 
 	cases := []struct {