Java, Python, and even Ruby [1] can get you under 10ms for service responses that actually hit a database, in my experience. But why improve performance by switching to a language that's well suited to the task at hand when you can do it by switching to a language that's hip?

[1] My company ran into a problem where one of our Ruby service responses was taking something about 100ms. We ruled out the database, and the ruby code, and finally discovered that the problem was jumping back and forth between Ruby and C while generating the JSON response from model classes with customized `to_json` behavior. We solved it by traversing the structure in Ruby and turning it into Arrays and Hashes. Back down under 10ms!