How to profile queries in a Rails 3 application

Question

How to profile queries in a Rails 3 application?

This answer only works in 2. *. How to do it in Rails 3?

Answer 1

The Rack Mini Profiler is really good: https://github.com/SamSaffron/MiniProfiler/tree/master/Ruby

Answer 2

I usually use the https://github.com/newrelic/rpm new relic. It tells you what is the slowest render call, and it also gives you which line in your code does exactly that. Very informative and easy to use.

Answer 3

Have you checked the built-in profiler?