This document provides guidelines and techniques for profiling and optimizing performance. It discusses measuring performance using tools like Chrome Developer Tools, optimizing assets by minifying files and images, improving database queries with indexing and caching, and profiling code with tools like XHProf and the Chrome CPU profiler. The overall guidelines emphasized are to measure everything, start optimizations in the front-end, avoid unnecessary work, and optimize code last.

1. PROFILING & OPTIMIZATION
Tools, guidelines, and techniques
Saturday, 9 November, 13

2. PERFORMANCE
Saturday, 9 November, 13

3. GETTING BUY-IN
Saturday, 9 November, 13

4. HIGHER CONVERSION RATES
Saturday, 9 November, 13

5. SLOW MOBILE
CONNECTIONS
Saturday, 9 November, 13

6. RULES; MORE LIKE
GUIDELINES
Saturday, 9 November, 13

7. Guideline
MEASURE EVERYTHING
Saturday, 9 November, 13

8. Guideline
HUNT THE BIG FISH
Saturday, 9 November, 13

9. Guideline
START CHEAP & ITERATE
Saturday, 9 November, 13

10. Cost Order
Minify assets
Compress images
Reduce number of HTTP requests
Optimize database queries
Add caching
Code optimization
Saturday, 9 November, 13

11. JUNK UP FRONT
Saturday, 9 November, 13

12. Junk Up Front
Saturday, 9 November, 13

13. Measuring
Chrome developer tools
Saturday, 9 November, 13

14. Junk up front
Number of requests
Number of hosts
Image count & image size
Script count & script size
Saturday, 9 November, 13

15. Fixing
Smushit (pngcrush, jpegtran, imagemagick)
Uglify.js, CSSMin
Make, phing, rake, grunt, shell scripts
Saturday, 9 November, 13

16. Image sprites
Easy way to reduce requests, and overall page size.
Data-URIs.
Icon WebFonts.
Saturday, 9 November, 13

17. Guideline
AVOID WORK TO GO FASTER
Saturday, 9 November, 13

18. WEBSERVER TRICKS
Saturday, 9 November, 13

19. Measuring
Chrome developer tools
Saturday, 9 November, 13

20. Webserver tricks
GZIP all the things.
Far Future cache headers.
Consider a CDN.
Saturday, 9 November, 13

21. SQL MOLASSES
Saturday, 9 November, 13

22. Database slowness
Many backend performance issues are caused by too many, or
slow queries.
Mysql has a pretty terrible query planner.
Sub-queries and derived table joins will eventually catch fire.
Slow query logs, mtop, or monitoring like new relic are your best
friend.
Saturday, 9 November, 13

23. Database slowness
Slow query logs - Percona makes great tools for MySQL.
Disable query caching.
Run EXPLAIN on slow queries.
Add indexes/tweak queries, and repeat.
Saturday, 9 November, 13

24. Explain Queries
Visual explain makes it easier.
Saturday, 9 November, 13

25. Indexes
Index commonly used columns.
Column order in matters in indexes.
Saturday, 9 November, 13

26. CACHING
Saturday, 9 November, 13

27. Caching
Can be expensive to rollout, if you need new infrastructure
Cache expiration is really really hard.
Saturday, 9 November, 13

28. What to Cache
Results that don’t change often
Use monitoring/analytics to find the busiest pages.
Start using caching there.
Expand once you’ve learned more.
Saturday, 9 November, 13

29. Where to cache
Hopefully in RAM
Failing that in shared memory
Disk :(
Saturday, 9 November, 13

30. Optimize cache use
Watch cache miss rate.
Tune cache expiration so you miss less often.
Saturday, 9 November, 13

31. Guideline
OPTIMIZE CODE LAST,
MOST OF THE TIME
Saturday, 9 November, 13

32. JAVASCRIPT
Saturday, 9 November, 13

33. PHP
Saturday, 9 November, 13

34. Javascript tools
Chrome dev tools are the gold standard.
CPU profiles are invaluable.
Heap comparisons can be used to find memory leaks.
Saturday, 9 November, 13

35. CPU Profiler
Chrome dev tools
Saturday, 9 November, 13

36. CPU Profiler
Chrome dev tools
Saturday, 9 November, 13

37. CPU Profiler
Chrome dev tools
Saturday, 9 November, 13

38. CPU Profiler
Chrome dev tools
Saturday, 9 November, 13

39. PHP TOOLS
Saturday, 9 November, 13

40. XHProf
PECL extension produced by Facebook.
Captures runtime metrics at a function level.
Possible to use in a sub-sample of production unlike xdebug.
Saturday, 9 November, 13

41. Xhgui
Nicer UI to XHProf data
Saturday, 9 November, 13

42. Xhgui
Nicer UI to XHProf data
Saturday, 9 November, 13

43. XDebug
Not suitable for servers with traffic,
Very detailed results.
Saturday, 9 November, 13

44. Webgrind
XDebug UI
Saturday, 9 November, 13

45. Other PHP tweaks
Opcode caching is a must.
Don’t use file based sessions.
Saturday, 9 November, 13

46. RECAP
Saturday, 9 November, 13

47. MEASURE EVERYTHING
Saturday, 9 November, 13

48. BE THRIFTY
Saturday, 9 November, 13

49. START IN THE FRONT
Saturday, 9 November, 13

50. AVOID WORK
Saturday, 9 November, 13

51. OPTIMIZE CODE
Saturday, 9 November, 13

52. THANKS
Saturday, 9 November, 13

53. Thanks
mark_story on Twitter.
markstory on Github.
Rate this talk: https://joind.in/9994
Saturday, 9 November, 13