1. @nwbower Bigger, Faster, and more Engaging while on a Budget! Nathan Bower

2. 2 Evolution of Page Weight and Requests: 3X increase in last 5 Years Image credit to HTTPArchive.org (http://httparchive.org/trends.php )http://httparchive.org/trends.php

3. 3 Reactive Measurements TOTO Images Credit: http://www.spc.noaa.gov/faq/tornado/toto.htm

4. 4 Frequent Measurements Image Credit: http://history.msfc.nasa.gov/saturn_apollo/photos/images/10075947_jpg.jpg

5. 5 Visible Measurements with Alarm

6. 6 Measure and Trend What’s Important! Bigger : Size, # of Requests All Resource Types by Weight and # of Requests –Images, Fonts, JavaScript, CSS, HTML, total size, total requests, etc. Faster : Time User Perceived Performance –Ex. “AFT Hero Image”, “AFT Search Box” SpeedIndex TTFB Pagespeed

7. 7 Tools for Measuring and Trending Synthetic Measurements SpeedCurve.com Independent WPT Instance  Graphite PhantomJS w/HAR  HARStorage WPT OR PhantomJS w/HAR  SPLUNK Real User Monitoring (RUM) Boomerang  SPLUNK Numerous companies offering RUM

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12. 12 Evaluate Performance Trade-offs More Engaging : Conversion Rates Jakob Nielsen “ Increased conversion is one of the strongest ROI arguments for better user experience and more user research. Track over time, because it's a relative metric. ” Trend and Correlate Traffic Patterns to Performance –PV/Session, Session Duration, Bounce Rate Observe Variations by Build Release Heavier and Slower Modifications May Improve Engagement! Prove changes through AB Testing

13. 13 What else should we budget? 3 rd Party Resources Service Response Time Database Query Time DNS Resolution SSL Negotiation TCP Connect HTTP Status Codes

14. 14 Responsive Design Mobile User Timing MarkDesktop User Timing Mark …wait, these are GOALS!

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19. 19 New Feature – AB Testing Showed Improved Engagement

20. 20 Business Intelligence – User Engagement Exceeded Budgets w/ vs w/out (11days prior vs 11days post) Device TypeUusSessionsDuration/Session (ms)PVs/SessionBounce RatePVs/Uus Phone2.31%2.42%1.86%-2.09%-1.20%-1.99% Tablet-0.95%-0.96%0.98%-3.64%0.52%-3.65%

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22. 22 SpeedIndex Did Not Falter Despite 4X Weight Increase

23. 23 RUM confirmed 10sec loss at 75 th Percentile for “Time to Onload”

24. 24 Lessons Learned Increase Frequency of Measurements, “Quick Response”! Budgets enable a “Call to Action”! Prioritize User Timing marks for user perceived performance. Excess resources on page load may not affect user perception of performance.

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26. 26 ZILLOW ENGINEERING BLOG ENGINEERING.ZILLOW.COM Come Join Our Team! Zillow.com/jobs

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