resque/resque-scheduler — pull request #454 by mjohnsen (2014-11-10 14:24:50+00:00)
Title: Memoized runtime_env in order to prevent premature garbage collection of Env instance, which leads to pidfile getting deleted while resque-scheduler is still running.

The premature deletion of the pidfile, in my experience, happens on RedHat 5.5, but does not happen on RedHat 6.5.