The document discusses how performance matters for websites and applications. It notes that additional page load time of 1 second can result in 7% lower conversion rates and 11% fewer page views, and that Amazon earns an additional $480 million per year from improving page load times by 100 milliseconds. It then provides tips to improve performance, such as reducing dependencies on external services, optimizing CSS, improving database queries, monitoring performance, and prioritizing performance work.

1. You’re here because
PERFORMANCE MATTERS

2. I’m here to convince you
SPEED IS A FEATURE

3. Chris Kelly
@amateurhuman

4. Start with the
FACTS

5. Additional page
load time
1s = 7% Loss in
conversions

6. Additional page
load time
1s = 11% Fewer
page views

7. -100ms
Page Load = +1%
Revenue
AMAZON
+$480M per year

8. Pause for a
CLICHÉ

9. Time is
Money

10. per • for • mance (noun)
1. a way to make more money
2. a way to work on stuff that
matters

11. A performant application has
a smaller footprint.
A smaller footprint means
less resources to manage.
Less resource management
means more time working on
the good stuff.

12. Built for
SPEED

13. Where does the time go?

14. 1. Slave to the man
2. Slave to the DOM
3. Slave to the data
4. Slave to the box
5. Slave to the network

15. Business in the
FRONT

16. The Internet is a distributed
system.
We’ve become dependent on external services:
analytics, ads, trackers, social.
Loading an external service can add over 900ms
to your load time.
Synchronous Javascript calls will block your
page load.

17. Facebook doesn’t always go down.
But when it does, it takes down the rest of
the Internet.

18. Get used to the
White Page of Death

19. CSS May Be Your
New Worst Enemy
Browsers block rendering until all CSS is
downloaded.
Browsers will download all CSS before
rendering, even if it is unused.
Does your mobile phone really need to
download the print stylesheet?

20. Party in the
BACK

21. Death by Database
N+1 queries will bring your database to its
knees.
Slow queries will kick it while it is down.
Disk thrashing will finish it off and pick it’s
pockets for good measure.

22. In the Cloud Resources
Are Limitless, Right?
Resources in the cloud are abundant but
inconsistent.
Failing resources create a domino effect of
further failures.
Scaling has more to do with people more than
any other resource.

23. There and Back Again,
A Network Tale
Network round-trips can add up quickly, even
within the same datacenter.
Browsers will limit simultaneous downloads
from the same host.
Service Oriented Architectures are pushing
more data through the network.

24. So, now what’s
NEXT

25. If you aren’t
monitoring, start!

26. Put performance in
your backlog.

27. Make performance
into a hack day.

28. Turn performance
into a feature.

29. Oh yeah, install
New Relic.

30. Get In Touch With Us
http://support.newrelic.com
support@newrelic.com
@newrelic

31. Sources and credit:
Some content for this presentation was graciously provided by:
http://www.readwriteweb.com/enterprise/2012/05/the-fastest-online-payment-processor-its-google.php
http://blog.newrelic.com/2011/12/22/are-external-services-slowing-you-down-new-relic-infographic-reveals-
the-fastest-and-most-popular-external-apis/
http://www.webperformancetoday.com/2012/05/29/browser-innovation-14-web-performance-rules-faster-
loading-websites/
http://blogs.keynote.com/the_watch/2012/06/facebook-failed-did-you-.html
http://www.phpied.com/css-and-the-critical-path/
http://dtrace.org/blogs/brendan/2012/02/29/the-use-method/
http://highscalability.com/blog/2012/5/16/big-list-of-20-common-bottlenecks.html
https://gist.github.com/2841832