subject: The Next Generation Of Performance Management [print this page] Being able to see page performance at this more granular level enables two significant types of insight. First, it enables a more accurate understanding of what the site experience is for the user, which can be represented in ways that are important to the businessnot just IT. Second, it can help site developers and operations teams work together to shave precious milliseconds from users perceived wait times.
Not all of this data is new. For some time, Keynote has measured and reported critical page-load milestones such as URL redirect time, resource timing, etc. Operations teams have long used this information to tune their websites and correct performance issues. But collaborating with developers on problems impacting user experience was more difficult.
Now operations teams can monitor, measure, and parse page performance in a way that offers a far more telling picture of user experienceinformation thats both actionable to developers, and of concern to business owners.
To give business owners this insight, Keynote in Transaction Perspective 11 leverages Navigation Timing to measure distinct phases of User Experience:
Time to First Paint: When the user sees something happening on the screen; the site has begun to render in response to their request. This critical first step tells the user that the site is responding to their action.
Time to Full Screen: When most users would perceive their browser space is filled above the fold; rendering may still be happening out of sight, but from the users perspective, theyre looking at a full page.
User Experience Time: The total elapsed time the page took to complete. The browser is done with the page and is now waiting for and responding to additional user input. This is analogous to the standard page load time or user time; it can also be used to measure a complete multi-page transaction.
In a hyper-impatient world where success for one website over another happens in the blink of an eye, a single page-load metric may not be precise enough to represent how a user experiences the page. With increasingly sophisticated websites, the perception of how quickly a page loads can be quite different from the reality of how it is technically fully loaded.
Theres a disconnect thats starting to happen between user experience metrics and performance metrics, Rushlo says. It used to be that they were both more or less synonymous, because you could measure performance and it was very close to what the user experienced.
In reality, though, because many things can be happening behind the scenes even as the user sees the page on the screen, the page load number may not reflect what the user is perceiving.
