The new Ruby on Rails patches by Acunote/Nimble Method are speeding up Ruby on Rails by a claimed 5X… a friend of mine tried just the ActiveRecord::Base change and reported this:
Yup. I actually just did the ActiveRecord::Base change alone and got a good boost. The code change is pretty solid too. That led me to seriously look at some other code as well. If you happen to use the acts_as_modified plugin anywhere, let me know, I have a simple fix for it as well. Between those two patches, my tests run about 20% faster.