Michael Mahemoff writes: To be effective, Rails cache sweepers need to be more fully understood.  They know no standard, so you must employ art. He goes on: Sweepers observe both your models and your controllers, but most workarounds focus on their controller nature.  Importantly: the sweeper must be explicitly added as an observer. Even more important is redux. Read all about [Rails cache sweeper redux] it.

Source: Ajaxian