1) Users expect web pages and interactions to load within 1 second or less for exceptional performance. 2) When loading a web page, many factors beyond a developer's control contribute to delay, including bandwidth, latency, third party content, and client-side processing. 3) To achieve exceptional performance, continuous optimization of all aspects that impact load time is required, from server-side processing to real user monitoring and benchmarking.

1. Why you have less than a second to
deliver exceptional performance

2. What is exceptional
performance?

3. I did my
homework

4. It depends …
Instantaneous
(0.1 s – 0.2 s)
Immediate
(0.5 s – 1 s)
Continuous
(2 s – 4 s)

5. Websites should
load in 2 to 4
seconds

6. Interactions should
take less than a
second

7. What do users say?

9. Consumer expectations for how How long consumers will
quickly a web page should load wait for a page to load
before abandoning
5% 1%
less than 1 second less than 1 second
1 second 12% 2%
1 second
2 seconds 30% 10%
2 seconds
3 seconds 36% 27%
3 seconds
More than 4 seconds 17%
More than 4 60%
seconds
0% 10% 20% 30% 40%
0% 20% 40% 60% 80%

10. People are not
clocks
(i.e. their time perception is not that precise)

11. The 20 percent rule
1.6 s 2s 2.4 s

12. Exceptional
performance starts at
1.6 seconds

13. You might think
this is a lot of time

14. It is not under your control
Your control ends here

15. Web Application Delivery Chain
Content
Internet
Server
Browser
Processing
3rd Party

16. How much time do
you really have?

17. Bandwidth and Latency

18. What to expect?
http://www.yuiblog.com/blog/2010/04/08/analyzing-bandwidth-and-latency/

19. Getting web content
Content
Icon: http://www.gettyicons.com/free-icon/112/hardware-icon-set/free-server-icon-png/

20. Adding two round trips
we are down to 1.4
seconds

21. We use more than one domain

22. We haven’t downloaded
anything yet

23. 200 kB at 1.5 Mb/s
take about a second

24. After content download
we have 0.3
seconds

25. What about 3rd
Party
content

26. It does not make us faster

27. Client side processing
~ 0.3 seconds

28. Wait …

29. … we now have 0.0
seconds left …

30. … and have not
considered server-side
processing

31. Is it impossible to be
exceptionally fast?

32. No, but it is hard

33. … really hard

34. How do we get there?

35. Do your homework
#wpo

36. … many people don’t

37. How good are we?

38. Are we done?

39. No, we need to look at
actual timings

40. What to look at?

41. Are we done now?

42. Now, we need to benchmark

43. … and optimize again

44. So now we are done?

45. We need to optimize
our site for all users

46. Real User Experience

47. But now …

48. We have to do this
continuously

49. Conclusion

50. “First and foremost, we believe that
speed is more than a feature. Speed is
the most important feature. If your
application is slow, people won’t use
it.”
“10 Golden Principles of Successful Web Apps”
Fred Wilson 19 year Venture Capitalist
3/20/2010
http://carsonified.com/blog/business/fred-wilsons-10-golden-principles-of-successful-web-apps/

51. Alois Reitbauer
@AloisReitbauer
alois.reitbauer@dynatrace.com
http://blog.dynatrace.com