Velocity 2009 took place last week in San Jose, with Jesse Robbins
and I serving as co-chairs. Back in
November 2008, while we were planning Velocity, I said I wanted to highlight “best practices in performance and operations that improve the user experience as well as the company’s bottom line.” Much of my work focuses on the how of improving performance – tips developers use to create even faster web sites. What’s been missing is the why. Why is it important for companies to focus on performance?
That question was answered at Velocity last week by speakers from AOL, Google, Microsoft, and Shopzilla.
- Eric Schurman (Bing) and Jake Brutlag (Google Search) co-presented results from latency experiments conducted independently on each site. Bing found that a 2 second slowdown changed queries/user by -1.8% and revenue/user by -4.3%. Google Search found that a 400 millisecond delay resulted in a -0.59% change in searches/user. What’s more, even after the delay was removed, these users still had -0.21% fewer searches, indicating that a slower user experience affects long term behavior. (video, slides)
- Dave Artz from AOL presented several performance suggestions. He concluded with statistics that show page views drop off as page load times increase. Users in the top decile of page load times view ~7.5 pages/visit. This drops to ~6 pages/visit in the 3rd decile, and bottoms out at ~5 pages/visit for users with the slowest page load times. (slides)
- Marissa Mayer shared several performance case studies from Google. One experiment increased the number of search results per page from 10 to 30, with a corresponding increase in page load times from 400 milliseconds to 900 milliseconds. This resulted in a 25% dropoff in first result page searches. Adding the checkout icon (a shopping cart) to search results made the page 2% slower with a corresponding 2% drop in searches/user. (Watch the video to see the clever workaround they found.) Image optimizations in Google Maps made the page 2-3x faster, with significant increase in user interaction with the site. (video, slides)
- Phil Dixon, from Shopzilla, had the most takeaway statistics about the impact of performance on the bottom line. A year-long performance redesign resulted in a 5 second speed up (from ~7 seconds to ~2 seconds). This resulted in a 25% increase in page views, a 7-12% increase in revenue, and a 50% reduction in hardware. This last point shows the win-win of performance improvements, increasing revenue while driving down operating costs. (video, slides)
These case studies provide real world numbers that show the benefits of making your site faster. Other Velocity sessions share techniques for implementing performance improvements, including sessions from me, Doug Crockford, and the Facebook and Google frontend teams. But what about the user experience? In his session, Matt Mullenweg (of WordPress fame) makes sure we remember the importance of how the user feels while interacting with our site:
That’s why [performance] is important and why we should be obsessed
and not be discouraged when it doesn’t change the funnel. My theory here
is when an interface is faster, you feel good. And ultimately what that
comes down to is you feel in control. The web app isn’t controlling me,
I’m controlling it. Ultimately that feeling of control translates to
happiness in everyone. In order to increase the happiness in the world,
we all have to keep working on this.
Thanks to the Velocity speakers & their organizations for overcoming the many challenges required to present this data for the first time. We’re now equipped with the financial justification, the technical know-how, and the visceral motivation to go out and make the Web a faster place. We’ll have more performance success stories next year. Your company could be one of them! Capture your performance improvements and bottom line impact. We’d love to hear from you at Velocity 2010.