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

golang.tokyo #11( https://techplay.jp/event/641403 )での発表資料です。

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/
14. $ go tool trace
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) }
23. ॲཧ࣌ؒ
24. ॲཧ࣌ؒ
25. ϓϩάϥϜ͕֬อͨ͠ώʔϓྖҬ
26. goroutineͷ਺ͱ࣮ߦ࣌ؒ
27. OSͷThreadͷ਺ͱ࣮ߦ࣌ؒ
28. Proc(CPU)Ͱॲཧ͍ͯ͠Δ಺༰
29. ͳΜ͔৭ʑͳ৘ใ
30. Goݴޠ͸ ׂΓͱؾܰʹ syscallΛݺͿ
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) }
44. GUIͰ֬ೝग़དྷΔʂ
45. GC
47. GC
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 }
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