I have bloat. Should I use Rack::Bug, MemoryLogic or Oink on Rails 3 app?

I have severe bloat, spending most of the day killing rack processes on my server. I need to figure out the cause. Most likely too many activerecord objects allocated in memory, to the point that rock process exceeds 1 gig of private dirty memory. Should I use Rack::Bug, MemoryLogic or Oink on Rails 3 app to pinpoint the problem?