$ go tool traceを使ってみよう/ Let's use go tool trace

Transcript

1. $ go tool trace
 ࢖ͬͯΈΑ͏ גࣜձࣾωΫετΧϨϯγʔ @nametake

2. ࣗݾ঺հ

3. @nametake

4. Goྺ1೥ͪΐͬͱ

5. ύϑΥʔϚϯεܭଌ

6. runtime/pprof net/http/pprof

7. package main import ( "log" "net/http" _ "net/http/pprof" "runtime" )

   func main() { runtime.SetBlockProfileRate(1) log.Println( http.ListenAndServe("0.0.0.0:6060", nil), ) }

8. localhost:6060/debug/pprof/

9. None
10. None
11. None
12. None
13. None

14. $ go tool trace

15. None

16. ࢖͍ํઆ໌

17. runtime/trace

18. package main import ( "os" "runtime/trace" ) func main() {

    f, err := os.Create("trace.out") if err != nil { panic(err) } defer f.Close() err = trace.Start(f) if err != nil { panic(err) } defer trace.Stop() }

19. $ go tool trace trace.out

20. ϑΝΠϧॻ͖ࠐΈ

21. f, err := os.Create("test.txt") if err != nil { panic(err)

    } defer f.Close() for i := 0; i < 100; i++ { fmt.Fprintf(f, "line number: %d\n", i) }
22. None

23. ॲཧ࣌ؒ

24. ॲཧ࣌ؒ

25. ϓϩάϥϜ͕֬อͨ͠ώʔϓྖҬ

26. goroutineͷ਺ͱ࣮ߦ࣌ؒ

27. OSͷThreadͷ਺ͱ࣮ߦ࣌ؒ

28. Proc(CPU)Ͱॲཧ͍ͯ͠Δ಺༰

29. ͳΜ͔৭ʑͳ৘ใ

30. Goݴޠ͸ ׂΓͱؾܰʹ syscallΛݺͿ

31. None

32. syscallͷݺͼग़͠

33. ͱͯ΋͋΍͍͠

34. syscallΛݺΜͰΔ

35. f, err := os.Create("test.txt") if err != nil { panic(err)

    } defer f.Close() for i := 0; i < 100; i++ { fmt.Fprintf(f, "line number: %d\n", i) }

36. f, err := os.Create("test.txt") if err != nil { panic(err)

    } defer f.Close() for i := 0; i < 100; i++ { fmt.Fprintf(f, "line number: %d\n", i) }

37. bufio

38. f, err := os.Create("test.txt") if err != nil { panic(err)

    } defer f.Close() w := bufio.NewWriter(f) defer w.Flush() for i := 0; i < 100; i++ { fmt.Fprintf(w, "line number: %d\n", i) }
39. None
40. None
41. None
42. None
43. None

44. GUIͰ֬ೝग़དྷΔʂ

45. GC

46. None

47. GC

48. None

49. GCຖʹ֬อ͠௚͍ͯ͠Δ

50. n := 400000 list := []int{} for i := 0;

    i < n; i++ { list = append(list, i) }

51. n := 400000 list := []int{} for i := 0;

    i < n; i++ { list = append(list, i) }

52. n := 400000 list := make([]int, n) for i :=

    0; i < n; i++ { list[i] = i }
53. None

54. GC͕ൃੜ͍ͯ͠ͳ͍

55. ࠷ॳʹΨοπϦྖҬ֬อ

56. 6ms → 2ms

57. ฒྻԽ

58. https://making.pusher.com/go-tool-trace/ Connʹॻ͖ࠐΈ

59. https://making.pusher.com/go-tool-trace/ ͜ͷ෦෼Ͱॻ͖ࠐΜͰ͍Δ

60. https://making.pusher.com/go-tool-trace/

61. https://making.pusher.com/go-tool-trace/ ଞͷϓϩηε࢖ͬͯͳ͍

62. https://making.pusher.com/go-tool-trace/

63. https://making.pusher.com/go-tool-trace/

64. https://making.pusher.com/go-tool-trace/ CPUΛແବͳ͘ར༻

65. ͍Ζ͍ΖΘ͔Δ

66. શ෦ͷ໰୊͕ Θ͔ΔΘ͚Ͱ͸ͳ͍

67. CPUͷ࢖༻཰͸ pprofͱ͔Λ ݟͨ΄͏͕͍͍

68. ϓϩάϥϜͷ ྲྀΕΛ஌Δ

69. ͱΓ͋͑ͣ ݟͯΈΔ͚ͩͰ΋ ͍͍͔΋

70. go traceͷ͜ͱɺ ࣌ʑͰ͍͍͔Β……ɹ ࢥ͍ग़͍ͯͩ͘͠͞