Defining Fast: The Hardest Problem in Performance Engineering

We all want fast sites, but what is fast? What is performant? We may know it when we see; yet quantifying and communicating about web performance effectively is still a challenge. In this talk, we will discuss our ever-evolving set of standards for what comprises a fast site. With special attention to the problems that ads and analytics present for publishers, we will discuss how antiquated notions of web performance are a ripe environment for abuses by 3rd party code. Finally, we will discuss techniques for improving performance monitoring as a tool for institutional change.

Transcript

1. Defining Fast
   The Hardest Problem in Performance Engineering
   Zack Tollman | Condé Nast
   

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2. Menu Master
   

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7. Time to
   Sammich
   

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12. The Load
    Event
    

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16. Golden Age of
    Performance Metrics
    

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17. Too Many
    Metrics
    

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18. JS Parse/Compile Time Load Time Start Render
    First Contentful Paint MS First Paint Total Byte Weight
    Time to Interactive First CPU Idle Hero Element Load Time
    DOM Content Loaded First Paint Total Requests
    Perceptual Speed Index First Meaningful Paint Speed Index
    

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19. Tools Are
    Fantastic
    

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20. What Should
    You Care
    About?
    

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21. Does the Page Appear
    to be Loading?
    

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22. Server Timing API - Time to First Byte
    Start Render - First Paint
    First Contentful Paint
    

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23. Can I see
    meaningful content?
    

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24. First Meaningful Paint
    Speed Index
    Element Timing API
    

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25. Can I click on
    or scroll the page?
    

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26. First CPU Idle
    First Input Delay
    Rage Clicks
    

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27. Does the page
    continue to be usable?
    

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28. Time to Interactive
    Long Tasks
    User Timing API
    

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30. Philip Walton
    User-centric Performance Metrics
    https://developers.google.com/web/fundamentals/performance/user-centric-performance-metrics
    

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31. Metrics Picked
    Now What?
    

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32. Measure
    The Metrics
    

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33. Synthetic And
    Real User
    Monitoring
    

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34. Location
    

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35. Network
    

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36. Device
    

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37. Browser
    

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38. Test Frequency
    

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39. RUM: Real User
    Monitoring
    

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40. Variance
    is Provided
    

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41. Instrumentation
    Challenges
    

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42. Test with Synthetic
    

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43. Verify with RUM
    

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44. Data
    

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45. mean median average
    percentiles
    standard deviation
    

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46. Consider
    Your Audience
    

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47. Report
    Raw Values
    

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49. Competitor
    Comparisons
    

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50. Percent
    Change
    

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51. Business
    metric correlations
    

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52. Defining Fast Defines Your
    Performance Culture
    

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53. Don't Let Others
    Define Your Culture
    

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54. speakerdeck.com/tollmanz
    

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