Keeping Wikipedia fast [WeLoveSpeed]

Transcript

1. Keeping Wikipedia fast Peter Hedenskog - @soulislove

2. Keeping Wikipedia fast Peter Hedenskog - @soulislove

3. @soulislove

4. @soulislove Sweden France

5. @soulislove

6. @soulislove

7. What to do? @soulislove

8. @soulislove

9. @soulislove

10. @soulislove NO!!!!!

11. @soulislove Jean Bernadotte?

12. @soulislove

13. @soulislove Sweden France

14. @soulislove

15. @soulislove

16. @soulislove

17. Lets talk about performance @soulislove

18. @soulislove Today Our setup RUM & Synthetic Learnings I’ve got

    the last four years Case study one regression

19. @soulislove https://news.ycombinator.com/item?id=20903868

20. @soulislove https://phabricator.wikimedia.org

21. @soulislove https://grafana.wikimedia.org

22. Why is performance important? @soulislove

23. We want to bring free knowledge to the world independently

    of where you live and your economic status. @soulislove

24. @soulislove

25. Engineers/dev cares too! @soulislove

26. Why is performance hard (for us)? @soulislove

27. Keeping Wikipedia fast @soulislove https://news.ycombinator.com/item?id=20903868 Keeping Wikipedia fast is easy

    right?

28. @soulislove

29. The Wikipedia Performance Team Challenge All Wikis are different (JS/CSS)

    All pages are different (JS/CSS) All users are different (JS/CSS) @soulislove

30. Our history of performance testing @soulislove

31. PHP -> RUM-> Synthetic @soulislove

32. RUM @soulislove

33. @soulislove Metrics from real users Sampled (1/100) Buckets: platform, browser,

    location https://github.com/wikimedia/mediawiki-extensions-NavigationTiming https://grafana.wikimedia.org/d/000000143/navigation-timing?refresh=5m&orgId=1

34. @soulislove

35. @soulislove

36. @soulislove

37. How we use RUM @soulislove Metrics from “all” users/scenarios Median,

    75, 95, 99 - percentiles Alert on regressions First Paint / LoadEventEnd BFF with synthetic

38. Synthetic testing @soulislove

39. @soulislove

40. @soulislove Browsertime + WebPageReplay

41. That flat line @soulislove

42. Deviation @soulislove

43. How we use synthetic @soulislove Fixing the chaos (or creating

    more?) Wayback machine Three URLs per alert First Visual Change BFF with RUM

44. Learnings: Synthetics @soulislove

45. Validate metrics! @soulislove

46. @soulislove

47. https://phabricator.wikimedia.org/T187981 @soulislove

48. @soulislove

49. page1 != page2 @soulislove

50. @soulislove Deviation

51. @soulislove User journey: second view

52. @soulislove User journey: second view

53. Server matters! @soulislove

54. 1. AWS vs GCS vs other cloud providers 2. Servers

    change over time (what runs on the same physical server?) 3. C4.xlarge != C4.xlarge @soulislove

55. @soulislove https://phabricator.wikimedia.org/T192138 https://phabricator.wikimedia.org/T192138 https://phabricator.wikimedia.org/T192138 https://youtu.be/pYbgcDfM2Ts?t=1575

56. Testing multiple steps are hard @soulislove

57. How long time do your user stay on each page?

    How long do browsers keep HTTP connections open? @soulislove

58. Browser versions matter @soulislove

59. None

60. Know when browsers are updated!!! @soulislove

61. Learnings: RUM @soulislove

62. RUM can be good for finding regressions @soulislove

63. None

64. User Timing API != what shows on screen @soulislove

65. @soulislove

66. New element timings are better! @soulislove

67. @soulislove

68. Browser versions are important @soulislove

69. @soulislove

70. @soulislove

71. The hidden tabs incident @soulislove

72. @soulislove The idea: async all the things … use setTimeout

    to run things later.

73. @soulislove https://phabricator.wikimedia.org/T146510 setTimeout

74. @soulislove https://phabricator.wikimedia.org/T146510

75. @soulislove 10% of the traffics opens in another tab!

76. What are we missing? @soulislove

77. @soulislove

78. @soulislove RUM Higher sample rate Buckets per page type Which

    metrics are important?

79. @soulislove Synthetic Real mobile phones (T197847) Easier for devs to

    add tests (T225416)

80. Case study: 3/9-2019 incident @soulislove https://phabricator.wikimedia.org/T231929

81. @soulislove Firefox

82. @soulislove Firefox

83. @soulislove Chrome

84. @soulislove Firefox

85. @soulislove WebPageTest

86. @soulislove

87. @soulislove TTFB? No: because visible with WebPageReplay

88. @soulislove ttfb?

89. @soulislove ttfb?

90. @soulislove ttfb?

91. @soulislove Screenshots/video Diff the HAR using https://compare.sitespeed.io or size per

    content type in Graphite

92. @soulislove ttfb?

93. @soulislove We got 311 span class=“cs1-visible-error”!!! Citation errors: not shown

    to readers https://en.wikipedia.org/wiki/Help:CS1_errors

94. @soulislove Credits Pippi and father - SVT Quick et Flupke

    - Hergé The king shouting - Expressen The scream - Edward Munch Napoleon - Horace Vernet Engineers India Space Shuttle - Expressen Various pictures of Carl Gustaf - Swedish tax payers through the apanage

95. @soulislove Questions?? @soulislove peter@wikimedia.org