We’ll start with the HTML5 navigation timing. This dataset is available in the newer Internet Explorer, Firefox, and Chrome browsers. It is not available on Safari or many of the mobile device browsers. What’s nice about it is that we can get full page load time in the browser and we can see breakouts of DNS lookup, redirect, SSL handshake, processing, and cache access timing. These measurements are taken on each page. There are element end times available through this API but one of the current weaknesses in the data is that we don’t get start times of the elements on the page, these measurements are called resource events. A good use of resource events will be to use them to gage the effects of partner infrastructures or third party components that are in your pages.
The beauty of these new datasets will become more evident when you see them all combined in one Foglight page. Think of looking at a bunch of hits or even a session in FxV today. Now think of that, already rich data, with supplemental data that comes right from the user’s desktop. If you thought Foglight allowed you to understand a lot more about what your user’s are experiencing, just wait until you get a look at this stuff.
As always feedback is welcomed and encouraged…