bf := bufio.NewReader(r)
	switch f := detect(bf); f {
	case formatGzip:
		gz, err := gzip.NewReader(bf)
		if err != nil {
			return err
		}
		defer gz.Close()
		r = gz
	case formatS2:
		r = s2.NewReader(bf)
	case formatZstd:
		// Limit to 16 MiB per stream.
		dec, err := zstd.NewReader(bf, zstd.WithDecoderMaxWindow(16<<20))
		if err != nil {

00000150  4c 99 35 1d ba 31 01 0c  48 d2 f2 88 22 9c 91 7d  |L.5..1..H..."..}|
00000160  e3 74 f9 b3 52 bf 0e 0b  e1 31 7c 2c cb fd f2 8c  |.t..R....1|,....|
00000170  bf 27 40 6d 26 b7 62 47  56 91 22 00 67 9a df 4f  |.'@m&.bGV.".g..O|
00000180  f0 47 57 3c a6 46 4d 16  f6 8d fc 2d 91 c4 1a bf  |.GW<.FM....-....|
00000190  38 63 ec 63 fe 97 14 80  aa 5b 60 ff c8 77 57 9c  |8c.c.....[`..wW.|

	newLevels().
		// Level 1: bf=5(sync)
		Add(5, false).
		// Level 2: bf=2(sync)
		Add(2, false).
		// Level 3: bf=2(sync)
		Add(2, false).
		Build().
		Run(t)
}

func TestParallel(t *testing.T) {
	// Root is always run sync.
	newLevels().
		// Level 1: bf=20(parallel)
		Add(20, true).
		// Level 2: bf=5(parallel)
		Add(5, true).
		// Level 3: bf=2(parallel)
		Add(2, true).
		Build().

}

func parseGoroutineType2(path string) (map[time.Duration][]string, error) {
	f, err := os.Open(path)
	if err != nil {
		return nil, err
	}

	bf := bytes.Buffer{}

	save := func(s string) {
		bf.WriteString(s + "\n")
	}
	reset := func() {
		bf.Reset()
	}

	ret := make(map[time.Duration][]string)

	s := bufio.NewScanner(f)
	s.Split(bufio.ScanLines)

	var (
		t            time.Duration

000002e0  20 53 87 e6 77 26 be 45  e4 6d 31 e3 bf 02 42 01  | S..w&.E.m1...B.|
000002f0  70 c5 97 3a e4 7b 80 2b  1b eb c9 b2 0a 79 92 2e  |p..:.{.+.....y..|
00000300  3d b1 4d 13 69 d2 60 a9  fd e9 66 56 83 e4 f5 6a  |=.M.i.`...fV...j|
00000310  ae cd 8b 94 9f 0b 70 81  b1 ed c6 0d 5f 33 42 04  |......p....._3B.|
00000320  3d f7 b6 d3 e9 09 b8 bf  43 8c 19 d5 7d 60 d6 a9  |=.......C...}`..|

6KZIr/45mjs6PNo+ekAaQbpDWkT+RqJIRknqS45NNk7aUIJS/6oGmg2KFHobaiJqKWowa+/796v/XAcMDswWfB48JfwtvDWM+40DnQutE80b7SP9LB00T+DYZNjo2WzZ8dp22vvbgN/gNuC94UThzOJT4tvjY+Pr5HPk/OWE5g3mlucf56noMui86//KM8xnzp/Q09ML1UPXe9m32+/eK+Bn4qPk4+cf6V/rn+3f8B/yY/Sn9uv5L/tz/bf// space9eaea0911d89d63-03-13 10:33:57 +0000CreatorPeter LedbrookFileTypeauto-03-13 10:40:48 +0000ModifierPeter LedbrookMovementHand-letterNSPaperSizesiz{612, 792}NSPrintReverseOrient{{-1102, -795}, {3330, 2418}}ClassGraffleShapes.CanvasBackgroundGrap{8,...

6KZIr/45mjs6PNo+ekAaQbpDWkT+RqJIRknqS45NNk7aUIJS/6oGmg2KFHobaiJqKWowa+/796v/XAcMDswWfB48JfwtvDWM+40DnQutE80b7SP9LB00T+DYZNjo2WzZ8dp22vvbgN/gNuC94UThzOJT4tvjY+Pr5HPk/OWE5g3mlucf56noMui86//KM8xnzp/Q09ML1UPXe9m32+/eK+Bn4qPk4+cf6V/rn+3f8B/yY/Sn9uv5L/tz/bf// space9eaea0911d89d63-02-06 14:02:09 +0000CreatorPeter LedbrookFileTypeauto-02-20 09:24:49 +0000ModifierPeter LedbrookMovementHand-letterNSPaperSizesiz{612, 792}NSPrintReverseOrient{{-1223, -810}, {3330, 2418}}ClassGraffleShapes.CanvasBackgroundGrap{-113,...

6KZIr/45mjs6PNo+ekAaQbpDWkT+RqJIRknqS45NNk7aUIJS/6oGmg2KFHobaiJqKWowa+/796v/XAcMDswWfB48JfwtvDWM+40DnQutE80b7SP9LB00T+DYZNjo2WzZ8dp22vvbgN/gNuC94UThzOJT4tvjY+Pr5HPk/OWE5g3mlucf56noMui86//KM8xnzp/Q09ML1UPXe9m32+/eK+Bn4qPk4+cf6V/rn+3f8B/yY/Sn9uv5L/tz/bf// space9eaea0911d89d63-03-13 10:04:20 +0000CreatorPeter LedbrookFileTypeauto-03-13 10:42:19 +0000ModifierPeter LedbrookMovementHand-letterNSPaperSizesiz{612, 792}NSPrintReverseOrient{{-1178, -1021}, {3330, 2418}}ClassGraffleShapes.CanvasBackgroundGrap{-68,...

00000070  e3 fd e6 a2 50 93 bf 87  85 60 e7 7f 0b a0 96 c4  |....P....`......|
00000080  29 55 63 de fe 6b 75 99  b2 a6 75 92 61 d0 96 19  |)Uc..ku...u.a...|
00000090  f5 60 8f ec e9 d3 98 4a  b9 6b 98 26 c1 3e 27 7e  |.`.....J.k.&.>'~|
000000a0  17 03 03 00 17 5a aa bb  35 67 ec 83 da 8e 85 bd  |.....Z..5g......|
000000b0  ae a5 0d c9 8b cd 03 bf  96 2b 35 61 17 03 03 02  |.........+5a....|

000000f0  92 85 d5 e0 7a cd da a6  c0 5a bf 8b eb 83 db a0  |....z....Z......|
00000100  dc c3 e2 a8 d5 ca ad 87  75 19 08 dd 3e 2e 36 a0  |........u...>.6.|
00000110  a1 53 28 09 cd 1c 1d a0  24 77 e3 e6 4d b1 8f 36  |.S(.....$w..M..6|
00000120  43 29 79 b3 e2 fb 9e dc  39 90 b5 b7 db 6d 0a c0  |C)y.....9....m..|
00000130  55 d2 1c fd 8d 57 5b bf  e3 70 b7 6a bc af 4f 34  |U....W[..p.j..O4|