Sometimes people ask if a web load testing tool supports JavaScript. They basically want to know if it is possible to apply the tool to test a web application implemented with JavaScript. The answer is usually obvious. Most load testing tools do not need to execute JavaScript code contained on web pages. This code is executed by the browser when the test is recorded.
So, the only requirement for the load testing tool is that it should be able to record all AJAX requests produces by the JavaScript code on the loaded page. These requests are used to update the page content in the browser. Since they carry additional data, they should be reproduced during the test when the user session is replayed. […]
