[trasz]

So essentially a whole another daemon/service designed to provide a fake permission system for real-time privileges?

[yrro]

Nothing fake about it? That is one of the actions that RealtimeKit allows clients to request:

    $ pkaction --action-id org.freedesktop.RealtimeKit1.acquire-high-priority --verbose org.freedesktop.RealtimeKit1.acquire-high-priority:
      description:       Grant high priority scheduling to a user process
      message:           Authentication is required to grant an application high priority scheduling
      vendor:            Lennart Poettering
      vendor_url:        
      icon:              
      implicit any:      no
      implicit inactive: yes
      implicit active:   yes

In the default configuration that will be granted to clients that are part of a local console session, but denied to clients that are not (e.g., batch jobs, SSH). That policy can be further customized by the OS vendor, organization, site, or local admin in quite a flexible way.