June 2012
Intermediate to advanced
226 pages
5h 5m
English
Content preview from Web Performance Daybook Volume 2Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Chapter 19. Stop Wasting Your Time Using the Google Analytics Site Speed Report
Since May 2011 the Site Speed report in Google Analytics shows how fast your pages load for your real visitors. Google Analytics measures page load time by using the Navigation Timing API (http://w3c-test.org/webperf/specs/NavigationTiming/) in all browsers that support it (IE9+, Chrome, FF7+, Android4+ (http://caniuse.com/#search=navigation)) and falls back to Google Toolbar data for older versions of IE and Firefox. Having page speed data in GA is great, because you can easily correlate it to bounce rate and conversion, resulting in great, actionable insight that down the road leads to a faster site, happier users, and more revenues. But if a significant percentage of your visitors use Firefox 7 or 8, you may very well be wasting a lot of time interpreting the Site Speed data and even more time taking the wrong actions.
Problem: A Bug in Firefox Implementation of the Navigation Timing API
Firefox implemented the Navigation Timing API in version 7, which
was released on September 27, 2011. From that day in that browser, there
has been a bug in the implementation of that API. You can read all about
it in the bug ticket (https://bugzilla.mozilla.org/show_bug.cgi?id=691547) on
Bugzilla. The problem is that the value for window.performance.timing.navigationStart can be
too low, which means it is too far in the past. Google Analytics uses a
simple formula to calculate page load time: loadTime = ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.