space , 96-128 for kernel threads, 128-191 for user real-time threads (SCHED_FIFO and SCHED_RR policies), and 192-223 for software interrupts . [ edit ] Solaris Solaris uses a multilevel feedback queue with priorities ranging from 0-169. 0-59 are reserved for time-shared threads, 60-99 for system threads, 100-159 for real-time threads, and