High Performance Web Sites blog

In YSlow! to YFast! in 45 minutes, Theo Schlossnagle (CEO of OmniTI) delivers a play-by-play about how he made his corporate web site 35% faster. The amazing revelation in his commentary is that he was able to complete all of these improvements while sitting in my workshop at Velocity (ahem).

OmniTI is a full service web house, specializing in web performance and scalability. The irony of the fact that their corp web site received a YSlow “F” wasn’t wasted on Theo. The cobbler’s children syndrome. (Same is true on my web site – I’ve got to optimize Wordpress!)

Theo walks through his changes one-by-one: adding a far future Expires header, removing ETags, compressing text responses especially scripts and stylesheets, and moving resources to a CDN without cookies. With less than 45 minutes work, his site went from a load time of 486 milliseconds down to 315 milliseconds.

There’s more low hanging fruit – consolidating scripts, consolidating stylesheets, and CSS sprites. But it’s great to get this early case study on specific improvements and their corresponding impact on performance. I hope he’ll share the results from the next wave of optimizations.

At OSCON last week, I attended Artur Bergman’s session about Varnish – A State of the Art High-Performance Reverse Proxy. Artur is the VP of Engineering and Operations at Wikia. He has been singing the praises of Varnish for awhile. It was great to see his experiences and resulting advice in one presentation. But what really caught my eye was his last slide:

Wikia measures exit rate – the percentage of users that leave the site from a given page. Here they show that exit rate drops as pages get faster. The exit rate goes from ~15% for a 2 second page to ~10% for a 1 second page. This is another data point to add to the list of stats from Velocity that show that faster pages is not only better for users, it’s better for business.

The last few months are a blur for me. I get through stages of life like this and look back and wonder how I ever made it through alive (and why I ever set myself up for such stress). The big activities that dominated my time were Even Faster Web Sites and Velocity.

Even Faster Web Sites

Even Faster Web Sites is my second book of web performance best practices. This is a follow-on to my first book, High Performance Web Sites. EFWS isn’t a second edition, it’s more like “Volume 2″. Both books contain 14 chapters, each chapter devoted to a separate performance topic. The best practices described in EFWS are completely new:

An exciting addition to EFWS is that six of the chapters were contributed by guest authors: Doug Crockford (Chap 1), Ben Galbraith and Dion Almaer (Chap 2), Nicholas Zakas (Chap 7), Dylan Schiemann (Chap 8), Tony Gentilcore (Chap 9), and Stoyan Stefanov and Nicole Sullivan (Chap 10). Web developers working on today’s content rich, dynamic web sites will benefit from the advice contained in Even Faster Web Sites.

Velocity

Velocity is the web performance and operations conference that I co-chair with Jesse Robbins. Jesse, former “Master of Disaster” at Amazon and current CEO of Opscode, runs the operations track. I ride herd on the performance side of the conference. This was the second year for Velocity. The first year was a home run, drawing 600 attendees (far more than expected – we only made 400 swag bags) and containing a ton of great talks. Velocity 2009 (held in San Jose June 22-24) was an even bigger success: more attendees (700), more sponsors, more talks, and an additional day for workshops.

The bright spot for me at Velocity was the fact that so many speakers offered up stats on how performance is critical to a company’s business. I wrote a blog post on O’Reilly Radar about this: Velocity and the Bottom Line. Here are some of the excerpted stats:

• Bing found that a 2 second slowdown caused a 4.3% reduction in revenue/user
• Google Search found that a 400 millisecond delay resulted in 0.59% fewer searches/user
• AOL revealed that users that experience the fastest page load times view 50% more pages/visit than users experiencing the slowest page load times
• Shopzilla undertook a massive performance redesign reducing page load times from ~7 seconds to ~2 seconds, with a corresponding 7-12% increase in revenue and 50% reduction in hardware costs

I love optimizing web performance because it raises the quality of engineering, reduces inefficiencies, and is better for the planet. But to get widespread adoption we need to motivate the non-engineering parts of the organization. That’s why these case studies on web performance improving the user experience as well as the company’s bottom line are important. I applaud these companies for not only tracking these results, but being willing to share them publicly. You can get more details from the Velocity videos and slides.

Back in the Saddle

Over the next six months, I’ll be focusing on open sourcing many of the tools I’ve soft launched, including UA Profiler, Cuzillion, Hammerhead, and Episodes. These are already “open source” per se, but they’re not active projects, with a code repository, bug database, roadmap, and active contributors. I plan on fixing that and will discuss this more during my presentation at OSCON this week. If you’re going to OSCON, I hope you’ll attend my session. If not, I’ll also be signing books at 1pm and providing performance consulting (for free!) at the Google booth at 3:30pm, both on Wednesday, July 22.

As you can see, even though Velocity and EFWS are behind me, there’s still a ton of work left to do. We’ll never be “done” fixing web performance. It’s like cleaning out your closets – they always fill up again. As we make our pages faster, some new challenge arises (mobile, rich media ads, emerging markets with poor connectivity) that requires more investigation and new solutions. Some people might find this depressing or daunting. Me? I’m psyched! ‘Scuse me while I roll up my sleeves.