Tools for Ajax load testing

Question

There seems to be a lot of stress/load testing tool that support AJAX.
I am wondering how well does these tool implemented.

Do they only record http request and repl

Answer 1

I've used Virtual User Generator, which is a part of the Loadrunner software from HP, to test AJAX applications. The software has several application protocols that can be used to record web applications, e.g. AJAX, and Click and Script.

For the majority of web application load testing it is sufficient to record and replay http requests. This will give the result of how the servers are handling the load. If your web application does a lot of asynchronous loading, and rendering on the client side, e.g. parsing large datasets of xml or json, or many DOM modifications, it can be relevant to include the browser tier to measure the end user experience.