I am wanting to load test a web based application that we are hosting on an IIS server (Windows 2003, IIS 6, PHP 5.2.0, MySQL 5.0.22).
What are the best tools for:
a) load testing
b) catching bottlenecks
c) catching memory leaks
Anything else I should be looking for?
UPDATE:
I found that MS Web App Stress tool was the best in my case as I could record header information and therefore the data that my Flash components were sending to some PHP pages that connect to the database. Selenium didn't record this for me. BrowserMob looks like a good service but again Selenium was not able to capture Flash in the same way as MSWAS.
JMeter from Apache http://jmeter.apache.org/ is really good at creating a load against a server.
It only however uses HTTP calls to do this and won't load test any of the AJAX parts of the application. There are other tools like PushToTest that can help with load testing against AJAX applications and if you don't want to worry about the hassle of setting up the machines you could use a service provider like BrowserMob. PushToTest and BrowserMob use Selenium to load test against your server so isn't IIS specific.
I hope that helps!
OpenSTA works pretty well, although it hasn't been updated in a while.