Unicorn is a Rack HTTP server for fast clients and Unix.
I was recently working on a project to build continuous integration performance tests on an application which makes extensive HTTP based calls to a middleware application. I was running in to issues where the middleware calls were unstable in the test, stage and load test environments. For the purpose of these tests, I was only interested in the render times of the Rails calls. The obvious choice seemed to cache the external HTTP requests.
I have been working on setting up RoR with MySQL on an AWS instance and ran in to some oddities, so I decided to document the steps I took and lay it all out real nice and pretty.