What Are Flame Graphs and How to Read Them - RubyConfBY 2017

A talk I gave at RubyConfBY in April 2017

https://www.youtube.com/watch?v=6uKZXIwd6M0

Further read:
- The Flame Graph: http://queue.acm.org/detail.cfm?id=2927301
- Blazing Performance with Flame Graphs (video): https://www.usenix.org/conference/lisa13/technical-sessions/plenary/gregg
- flamegraph gem: https://github.com/SamSaffron/flamegraph
- rack-mini-profiler: https://github.com/MiniProfiler/rack-mini-profiler
- ruby-prof-flamegraph: https://github.com/oozou/ruby-prof-flamegraph

Transcript

1. ! @mr_foto
2. " @mr_foto
3. HOW YOU REMEMBER SLOVENIA
4. HOW I REMEMBER BELARUS
5. @mr_foto Software Developer Team Lead Git Blame Navigator Time Zone Resolver
6. @mr_foto Software Developer Team Lead Git Blame Navigator Time Zone Resolver Slack Emoji Creator
7. #
9. $FLAME GRAPHS$
10. WHY AND WHAT Interactive visualization of stack traces From beginners to experts How SW is consuming CPU Brendan Gregg
16. SAMPLING My Day Reading Emails
17. My Day Reading Emails Replying to Emails SAMPLING
18. My Day Writing Code SAMPLING
19. My Day Writing Code Writing Tests SAMPLING
20. My Day Writing Code Writing Tests Running Tests SAMPLING
21. My Day Writing Code Writing Tests Running Tests Fixing Tests SAMPLING
22. My Day Writing Code Running Tests SAMPLING
23. My Day Making Espresso SAMPLING
24. SAMPLING My Day Reading Emails
25. My Day Writing Code SAMPLING
26. My Day Writing Code Running Tests SAMPLING
27. My Day Reading Emails Replying to Emails SAMPLING
28. GROUPING
29. GROUPING
30. GROUPING My Day Reading Emails Replying Writing Code ☕ Writing Tests Running Running Fix
31. FLAME GRAPH Function
32. FLAME GRAPH Function
33. FLAME GRAPH Function
34. FLAME GRAPH Stack Depth
35. FLAME GRAPH Stack Depth
36. FLAME GRAPH Stack Depth
37. FLAME GRAPH Stack Depth
38. FLAME GRAPH Ordered by Alphabet
39. FLAME GRAPH Ordered by Alphabet
40. FLAME GRAPH Total Time on CPU
41. FLAME GRAPH Total Time on CPU
42. FLAME GRAPH Total Time on CPU
43. WHO WANTS A T-SHIRT?
45. Q&A Q: Which function is on CPU the most?
46. Q&A A: f() top edge shows what is on CPU directly
47. Q&A Q: Why is f() on CPU?
48. Q&A A: a() → b() → c() → e() → f() f() was called by e(), e() was called by c(),…
49. Q&A Q: How does b() compare to g()?
50. Q&A A: b() looks like it is running (present) about 10 times more often than g()
51. USING WITH RUBY Sam Saffron gem 'flamegraph' Flamegraph.generate(filename) do # your work here end
52. TOPTAL.BLOG
53. ORIGINAL 1.083 (± 0.0%) i/s - 33.000 in 30.86s
54. CACHE KRAMDOWN 8.368 (±12.0%) i/s - 244.000 in 30.04s
55. CACHE KRAMDOWN 8.368 (±12.0%) i/s - 244.000 in 30.04s 7.5x improvement
56. MEMOIZATION & CO. 10.140(± 9.9%) i/s - 292.000 in 30.03s
57. MEMOIZATION & CO. 10.140(± 9.9%) i/s - 292.000 in 30.03s 9.4x improvement
58. NOW WHAT? You’re here Ask me Ask someone smarter than me Ask anyone else Read/watch blog posts/videos
59. I ❤ ☕
60. I ❤ ⌨
61. I ❤ (
62. I ❤ )
63. http://mr.si/
 @mr_foto THANK YOU