experimenting with optimizing some areas that involve long processing times on some SQL selects (or any background task, really). This is in Rails 4.0.0 with Ruby 2.0.0p247, PostgreSQL 9.2.4.
In this case, I can do intelligent dividing of selects to even the workload among N processes for the DB backend.
I currently am trying Spawnling, and this works for exactly one hit before I have to restart the web service:
spawns =  ABC.each do # criteria for selects to divide load spawns