yahoo performance-team proved this very well.
surf with their first computer bought 7 years ago at Interdiscount and is mostly surfing on the developers least favourite browser (like IE 6). As a result, those visitors often do not get the optimal user-experience and the website loses traffic (=money).
The conclusion out of this is:
- We have to optimize our page following yahoo’s findings.
Where to start?
Most of our traffic is generated through the photo album. We analyzed and improved following use-case in terms of loading-speed and responsiveness:
User comes to homepage…
…goes to the a photoalbum…
…clicks through the photos
We then did the following things:
- reduced amount of external scripts (like Google Analytics) or load them after everything else to reduce the dependency on third party hosts
- reduced DOM-operations
- reduced amount of written code by refactoring
- found and removed some common memory leak-patterns
- removed fancy fading-effects as they were useless and took a lot of CPU time
For example on IE7
(50% of our users are using it) we had following improvements:
- time loading and set up the photoalbum decreased from 4.8 to 2.9 seconds
- time switching between thumbnailpages decreased from 1.3 to 0.3 seconds
Once we released the tweaks, the pageviews per visit increased by 20%.