Hacking to be Performant? Talk presented at Meta Refresh 2015 Delhi Runup hosted at Wingify. Presentation discusses the different hacks and approaches available to make your Application performant, but what are the different pros and cons related to each approach.

1. Hacking to be Performant?
Talk: Performance Engineering

2. Speaker: Apoorv Saxena

4. Time to run a poll

5. How many you consider
#perfmatters?

6. What performance
monitoring tools are you
using?
(To evaluate your Front End’s Performance)

7. How many of you have it as
part of your
“Continuous Deployment”?

8. Enough, let’s start Hacking

9. What do you mean by
“Hacking”?

10. What do you mean by
“Performant”?

11. Evolution of the Web: Browser & Technologies

12. Evolution
Is necessary, though it proceeds gradually and
takes some time, it accounts for everyone to be
on the same page.
Though, not everyone can afford to walk at the
same speed, they must run, jump obstacles, cut
corners and give their best shot.

13. Loading Webpages under
1 second

14. First pixel render time less
than 500ms

15. Running Applications at
60fps
Delivering a Jank Free Experience

16. #perfmatters

17. What are we Trying to fit?
● HTML5 Games
● Single Page Applications
● Animations
● Editors, Document Collaboration Tools
● WebRTC (Video, Audio)
and many more.

18. That’s it?
Not at all.
Everything available on Mobile must be
available via APIs on Web.

19. Let me tell you a story

20. From JS to Screen:
Style/Layout PaintingJS Compositing
keep < 16ms!
1. Add CSS rules in style via JS.
2. Recalculate style, maybe relayout.
3. Paint the browser’s mental model to a layer
4. Composite all layers into a final image

21. What causes Jank?
Style/Layout PaintingJS
16ms!

22. Draw
Commands CPU GPU
SCREEN
Extensive Upload
Rasterization in
Action

23. Performance Hacks:

24. Creating a separate layer for
elements requesting
frequent updates

26. Hardware Acceleration
rules me

27. What about using Canvas
instead of DOM?

28. You must consider:
● Accessibility, Flipboard injects mirror of the content into an
invisible dom so it’s still in synch for VoiceOver.
● Canvas is not hardware accelerated on every browser
(accompanies device constraints).
DOM Rendering might become amazingly fast soon.
(Hint: remember project Ganesh).

29. Considered using DOMSprites?

31. SCREEN
Project Ganesh:
Draw
Commands GPU

32. 60fps is not required at every instance

34. Note:
Our eyes are much more attuned to variance
than framerate.
A steady 30Hz looks better than 60Hz that
misses a few frames a second.

35. Thank You!
See jankfree.org, html5rocks.com for lots of info