Breaking news at 1000ms - Front-Trends 2014

An introduction into how the Guardian are making their next generation website load as fast as possible, and ultimately breaking the news to the user within 1000ms.

During the talk you will discover why performance matters, what are the common performance bottlenecks in the browser from networking to painting and learn how to best optimise and monitor each stage of the critical path to create fast, jank free websites.

Transcript

1. Breaking news at 1000ms @patrickhamann - FrontTrends - May 2014
3. next.theguardian.com
4. 100million
6. 0 2.25 4.5 6.75 9 2000 2006 2009 2012 User load time expectations (Secs) User load time expectations are decreasing Source: Web Performance Today - March 2013
7. 0 5000 10000 15000 20000 Jan Feb Mar Apr 10% Percentile Median 90% Percentile Average SpeedIndex top 10,000 websites Source: HTTPArchive - May 2014
8. Maslow's hierarchy of user needs • We surveyed 3000 users • About 17 key product drivers • They rated speed 2nd most important • Only after easy to find content
9. Time & user perception Delay User perception 0–100 ms Instant 100–300 ms Small perceptible delay 300–1000 ms Machine is working 1,000+ ms Likely mental context switch 10,000+ ms Task is abandoned Source: Ilya Grigorik – High-Performance Browser Networking
10. 1000ms
11. A performance budget https://flic.kr/p/iQ69Kg
12. – Tim Kaldec - 2013 A performance budget is just what it sounds like: you set a “budget” on your page and do not allow the page to exceed that. This may be a specific load time, but it is usually an easier conversation to have when you break the budget down into the number of requests or size of the page.
13. Setting a budget https://flic.kr/p/eHsirY
14. 1. Core content should be delivered first 2. Core content should render within 1000ms 3. Every feature must fail gracefully 4. Every request should be measured
15. 1. Core content should be delivered first 2. Core content should render within 1000ms 3. Every feature must fail gracefully 4. Every request should be measured
17. User Content API Popular Comments Article DB DB
18. https://flic.kr/p/77ZtUH
19. User Content API Popular Comments Article DB DB
20. Final progressively enhanced page Initial page payload
22. 1. Core content should be delivered first 2. Core content should render within 1000ms 3. Every feature must fail gracefully 4. Every request should be measured
23. Browser rendering 101
24. Source: Google - Pagespeed Insights
25. Network JavaScript Render tree Layout Paint HTML DOM CSS CSSOM Network JavaScript Render tree Layout Paint HTML DOM CSS CSSOM Network JavaScript Render tree Layout Paint HTML DOM CSS CSSOM DOM
26. JS CSS HTML CSS & JS § HTML async DOMContentReady Start render
27. Get the CSS down as soon as possible.
28. What is your critical CSS?
29. Popular content ✘ Sharing ✘ Comments ✘ Related content ✘ Commercial components ✘ Article ✔
30. What if we inlined our critical CSS?
31. WTF%$?! Inline critical CSS
32. 0.9 1.0 1.1 0.9 1.0 1.1
35. Load time First byte Start render Visually complete 3.366s 0.204s 1.113s 3.700s Before Load time First byte Start render Visually complete 3.017s 0.262s 0.759s 2.00s After
36. Use MD5 hash for cache key WTF no stylesheets?
37. What does the future hold?
38. http/2
39. 1. Core content should be delivered first 2. Core content should render within 1000ms 3. Every feature must fail gracefully 4. Every request should be measured
40. Story of my life
41. – W3C Font Spec ! ! ! User agents may render text as it would be rendered if downloadable font resources are not available or they may render text transparently with fallback fonts to avoid a flash of text using a fallback font. ! In cases where the font download fails user agents must display text, simply leaving transparent text is considered non-conformant behaviour.
42. Font loading 101 IE Firefox WebKit Blink Blocking ✗ ✔ ✔ ✔ Timeout – 3s – – Source: Ian Feather – Web fonts and the Critical Path
43. guardian egyptian
44. progressive enhancement https://flic.kr/p/9RDXVd
45. Is modern browser? Support WOFF? Font in localStorage? Show font Show fallback Download JSON localStorage space? Cache in localStorage
46. Example of base64 json’ifed fonts
47. service worker Webfontjson
48. What does the future hold?
49. Font load events
50. service worker ServiceWorker
51. 1. Core content should be delivered first 2. Core content should render within 1000ms 3. Every feature must fail gracefully 4. Every request should be measured
52. assets radiator
53. R.U.M. (real user metrics)
56. speedcurve
59. What does the future hold?
60. Resource Timing API
61. Beacon API
62. 1. Core content should be delivered first 2. Core content should render within 1000ms 3. Every feature must fail gracefully 4. Every request should be measured
63. Takeaways
64. Everyone must be involved by baking performance into your workflow from day one.
65. Deliver core content first,
 then progressively enhance the extras.
66. Set a performance budget.
 Measure, optimise & repeat!
67. Performance is a requirement; not a feature.
68. Thank you. Questions? @patrickhamann - http://github.com/guardian/frontend g We’re hiring!