Maintaining a performance budget

The average page weight and number of connections on a website keep increasing. It’s not unusual to see a website download 10mb to your device, which could take several minutes. Even more so if you’re on a mobile device with a bad connection. Needless to say, we want to make sure cybex-online.com stays lightning-fast.

To do this we want to maintain a performance budget. For instance, no page is allowed a pageload time above three seconds. Or a page should contain no more than 3mb of data in total. Or any page should be usable within ten seconds on a 3G connection.

Any time we want to add a feature, we must stay within our page budget. If the feature would break the budget, there are three options:

• Optimize the feature (redesign and refactor)
• Remove another feature
• Don’t add the feature