Digibury Talk Scaling Websites - Deri Jones, CEO SciVisum Ltd Deri Jones is a renowned speaker and thought-leader in the Web performance arena. In his Digibury talk he not only covered war-stories from many years in the web performance space, he also gave tips on making any page fast, and explained how to use open-source tools in addressing the challenges of scaling websites.

1. MAKING YOUR WEBSITE FAST - AND SCALABLE
Deri Jones
Digibury January 2015

2. Tue Feb 3rd

3. WEBSITE SPEED

Black Friday and Xmas peaks

4. UNACCEPTABLE DELAYS

5. THE NEED FOR SPEED

Impatience

SEO

6. THE NEED FOR SPEED

Impatience

SEO

UX is the final USP

7. Your
UX
Your
offering

8. What makes sites slow ?

9. Network effects

ADSL 3G 4G

10. LATENCY

11. LATENCY TARGETS

Backbone best:

Local:
− ADSL 25 mS
− Mobile 250 mS

12. Network effects

Bulky: Images

Too many objects

Not using HTTP Keep alive

13. FIREBUG / DEVTOOLS

15. Browser effects

Objects block

Rendering time

16. 3RD
PARTY SCRIPTS

17. The offender:

<script src="http://3rdparty.com/script.js"></script>

18. Old solution
These days
<script async defer src="siteScript.js" onload="myInit()"></script>
These days:

19. Browser effects

Objects block

Rendering time

3rd
party blocking

20. AD SERVING IS SLOW
And no political motive to be faster
Will get slower as big-Data progresses

21. RESPONSIVE WEB
Avoid the Whitehouse.org story...

22. Can be good:

Painless install

Many configuration choices
Can be tricky:

Embedded CSS obsession

23. TOOLS

Firebug, DevTools

HTTPArchive.org

Webpagetest.org

24. DESIGNERS VS SPEEDERS

25. CHALLENGES

Responsive web:
− Better than 2 sites www. and m.

27. WEBSITE SCALING

28. SURPRISING LESSONS

Cloud auto-scaling – doesn't work

29. SURPRISING LESSONS
Cloud auto-scaling – doesn't work
− Scales too late
− Allows rest of farm to die
− Small print:
− Strictly 'very often' doesn't work

30. SURPISING LESSONS

Cloud auto-scaling – doesn't work
− Scales too late
− Allows rest of farm to die

31. CLOUD AUTO-SCALING

Uncertain spin-up time

DOA

32. SCALING

Don't obsess Disk IO
− Yes it's moving metal
− Web is a lot about static content

33. SCALING

The code platforms are good

Many problems in SysAdmin configs

CDNs
− Cache-Miss hurts

But don't assume!

34. SCALING

Many big hosters:
− Not motivated to help you

35. SCALING

36. USERS' EXPERIENCE
It's both:

The new battleground

A challenge
− Single Page website
− Offline-cache content
− Users' journeys complexity

37. USER EXPERIENCE

Cultural shift
− Make every one responsible for it!

Performance is a deliverable
− Test every release
− Continuous Integration

38. USER EXPERIENCE

Hard

Easier to save timings in your code
− ElasticSearch, Graphite

RUM and Analytics help

39. USER EXPERIENCE

'Do what your Customers do'
− more Synthetic monitoring
− For another day ...

40. RESOURCES

London Web performance meetup
− http://www.meetup.com/London-Web-Performance-Group

Third Party Footprints
− http://www.slideshare.net/bbinto/third-party-footprint-evaluating-the-

HTTP Archive
− https://speakerdeck.com/deanohume/the-good-the-bad-and-the-ug