What is a good approach for a performance testing tool suite for web applications? I am specifically interested in tools that execute a certain set of tasks well as opposed to tuning high traffic sites. In other words, a profiler would be a good idea to have, although I understand these tools are specific to a language. A profiler will help me understand where most time is spent in executing a particular part of the code, but does not provide me with a start-to-end view of where performance could be improved. Is there a tool that provides profiling data on where in the chain browser, web server, application server, database server most time is spent?

Thanks in advance

I came across this page earlier:

15 Tools to Help You Develop Faster Web Pages - Six Revisions

though I have no experience with most of the tools listed. HTH.

Thanks for the swift response. These days it is hard to see how web sites can be developed without Firebug and YSlow is an excellent add-on to Firefox. Some of the other tools in the list I was not aware of and will check them. Some of those remaining tools have not been maintained for a while, such as httperf.

I have also extensively checked the listings at opensourcetesting.org, but the vast majority is either ill-maintained, dependent on Java/Python or Windows or only measure responses for stress tests.

Depending on the web application, most have databases in the backend, so you will need a good database performance tuning tool.

I posted a few a few months back, mysqltuner.pl and tuning-primer.sh for MySQL.

Such tool for profiling most of the tiers will be very paid I suggest that you go for the DB scripts suggested by Neo in the previous post, and use apache's Jmeter for web profiling - very good alternative to the paid ones. OpenSTA is also a good tool, according to my colleagues, but personally I haven't used it.