jmeter

While Mercury has previously demonstrated the raw power of Varnish to radically accelerate the delivery of cached pages with Pressflow, that's only part of the battle for high performance Drupal. Cached pages need to be generated at least once, and logged in users will be bypassing Varnish when making requests. While it's nice to know you're covered for massive traffic spikes, what about baseline load?

Well, we want to answer that question too. Keep in mind that depending on your module/theme stack, your mileage may vary. A lot. Performance tuning a complex Drupal site for logged-in traffic requires sustained diligence at the application level — code profiling, slow query log review, innovative app-specific caches, etc — as well as hardware and system optimization. However, to set some baseline expectations, we used Jacob Singh's greate starter test suite and checked out a Mercury install on a 512MB Slicehost VPS. The results are quite encouraging.

In my never-ending quest to run larger and more complex drupal stacks for more and more users, I'm starting to hit the wall in what I'm able to accomplish with good old Siege, which has been my command-line tool of choice for benchmarking and performance testing for the past couple years. In particular, it breaks down too often in high-load simulations, and doesn't allow for any complex multi-threaded testing, making it very difficult to model near-reality user scenarios like "10 logged in users + 100 anons".

Lately, I've been getting into Jmeter, which has a lot more bells and whistles -- including a GUI! -- and which I think can offer a lot to Drupal developers. However, their basic web test plan barely scratches the surface of what's possible. With the right configuration, jmeter can effectively simulate complete user-behavior patterns like logging in, posting comments, etc.

I'm just getting started, but am curious if people "out there" are already way ahead of me, or if not if folks are interested in seeing the results of my testing work?