The new Yahoo! homepage, released in 2009, had a high bar to meet in terms of performance. The classic version of the page, a mostly static one, set lofty expectations for the newer version. Even though the new page has more options for customization and personalization, as well as being far more interactive, the performance goals remained the same. The team planned for performance from the beginning, laying groundwork that would allow us to avoid common performance pitfalls.
The team scoured Yahoo!’s Exception Performance guidelines and went beyond them, coming up with several twists that introduced incremental performance improvements. Every byte was counted, everything measured, to ensure we could meet the previous version’s metrics.
In this talk, I’ll go over the tactics that we took and the performance differences we made. Some of the topics include:
- How we decreased the average time to open up an application from 7 seconds to less than 2.
- How lazy loading of resources sped up the user experience.
- How we progressively trimmed kilobytes of data from the initial payload.
- How we changed our page flushing strategy to alter perceived performance.