-@node 4.4BSD Scheduler, Coding Standards, References, Top
+@node 4.4BSD Scheduler
@appendix 4.4@acronym{BSD} Scheduler
@iftex
with all these requirements simultaneously.
For project 1, you must implement the scheduler described in this
-appendix. Our scheduler resembles the one described in @bibref{4.4BSD},
+appendix. Our scheduler resembles the one described in @bibref{McKusick},
which is one example of a @dfn{multilevel feedback queue} scheduler.
This type of scheduler maintains several queues of ready-to-run threads,
where each queue holds threads with a different priority. At any given
Every thread has a @var{nice} value between -20 and 20 directly under
its control. Each thread also has a priority, between 0
(@code{PRI_MIN}) through 63 (@code{PRI_MAX}), which is recalculated
-using the following formula whenever the value of either variable term
-changes:
+using the following formula every fourth tick:
@center @t{@var{priority} = @code{PRI_MAX} - (@var{recent_cpu} / 4) - (@var{nice} * 2)}.