It was added for some workloads, but ill-suited and never really
got traction. Using cgroups to manage the resources of particular
services (using systemd), or something separate like rtkit is
a better bet.
This allows session power managers to do different actions depending on whether the user
is suspending or hibernating. This allows the session policy agent to poke other things
(for instance, the screensaver) even if another process initiated the sleep.
This is based on a patch from Phillip Susi <psusi@cfl.rr.com>, many thanks.
