Overview on why web performance matters, how to measure it and some discussion on 3rd-party content.
Presented t the DC area Web Manager's Roundtable group on 12/7/2011.
5. Google Search
en.oreilly.com/velocity2009/public/schedule/detail/8523
6. Yahoo
400ms slower =
5-9% drop
in full-page traffic
slideshare.net/stoyan/dont-make-me-wait-or-building-highperformance-web-applications
7. Firefox Downloads
…shaved 2.2 seconds off
the average page load
time and increased
download conversions by
15.4%!
blog.mozilla.com/metrics/2010/04/05/firefox-page-load-speed-%E2%80%93-part-ii/
10. MSN
Delayed loading of the Big Upper Right Ad by 1s
Time to Page Time to Page Page Ad Click Thru
Bottom Onload Clicks Views Rate
80ms gain 500ms gain +0.5% +0.4% -15%
velocityconf.com/velocity2011/public/schedule/detail/18039
11. AutoAnything
…cut AutoAnything’s web
page load times in half,
which resulted in a 9%
increase in conversion
rate, an 11% increase in
average ticket size, and a
12-13% increase in sales.
www.strangeloopnetworks.com/customers/autoanything-cuts-page-load-time-in-half-and-revs-up-sales-by-13/
13. SEO
…we've decided to take
site speed into account
in our search rankings.
googlewebmastercentral.blogspot.com/2010/04/using-site-speed-in-web-search-ranking.html
21. Active Testing
• Consistent results
• Good for detecting and diagnosing issues that are 100%
repeatable and on pages you are monitoring
• Lots of detail
• Availability monitoring
• Not representative of actual end-user performance
• Usually tested from data centers
• Sometimes co-located with CDN provider equipment
22. Synthetic Browsers
• Know HOW your active testing is done
• Some only test the base page
• Synthetic browsers usually not reflective of real browser
• Real browser testing
• www.engadget.com
• Synthetic Browser: 447 requests
• IE 8: 241 requests
23. Real User Monitoring (RUM)
• Full coverage on all pages visited by users
• Real performance information for end-user experience
• No availability monitoring
• Fluctuates Significantly
• Limited detail
• … but getting better
29. Frontend Single Point of Failure
Browser will stop processing for 20s (windows) – 90s (Mac)
<script type="text/javascript" src="http://platform.twitter.com/widgets.js"></script>
vs.
<script type="text/javascript">
(function() {
var tw = document.createElement('script');
tw.type = 'text/javascript';
tw.src = 'http://platform.twitter.com/widgets.js';
var s = document.getElementsByTagName('script')[0];
s.parentNode.insertBefore(tw, s);
})();
</script>
Browser will continue processing and not wait
30. What it feels like
http://www.webpagetest.org/video/embed/111011_bf3554f35b6e71a77f59e3719ee4e810b7226402