Below you will find pages that utilize the taxonomy term “tools”
Performance Resource Timing, Cors, and AJAX requests
This is a quick summary of a caveat of cross-origin resource sharing (CORS) when measuring performance of ajax requests using performance resource timings in the browser. To be clear in this article we will unpack slightly some of the information from Mozilla’s documentation on the subject. Why? While it contains the root cause it does not spell out the consequence, which hopefully we’ll do here. Resource Timing API wait what?! The rise and influence of performance measuring and monitoring across the discipline of web engineering has meant the respective tooling has come a long way too.
Real User Monitoring vs Synthetic Web Performance Tools
Let’s start with an assertion: Web performance is important. You agree with that and that’s why you’re here. Both real user monitoring and synthetic web performance tooling offer ways to shed light on how your website is performing for your users. Which to use? Easy, they offer different views and are both important. A simple way to differentiate is tools measure and evaluate, and monitoring tracks trends and deviations. If I may insert a pedantic opinion here, the former is best suited to build time and the latter for your production website.