VMS Help SHOW, SYSTEM, Qualifiers, /SCHEDULING_CLASS  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /SCHEDULING_CLASS[=class_name]
       /NOSCHEDULING_CLASS

    Displays processes that belong to a specific scheduling class
    (class_name). If the class name is not specified, all class
    scheduled processes are displayed along with the name of their
    scheduling class.