received ``recently,'' with the rate of decay inversely proportional to
the number of threads competing for the CPU.
-Because of assumptions made by some of the tests, @var{recent_cpu} must
-be updated exactly when the system tick counter reaches a multiple of a
-second, that is, when @code{timer_ticks () % TIMER_FREQ == 0}, and not
-at any other time.
+Assumptions made by some of the tests require that updates to
+@var{recent_cpu} be made exactly when the system tick counter reaches a
+multiple of a second, that is, when @code{timer_ticks () % TIMER_FREQ ==
+0}, and not at any other time.
-Take note that @var{recent_cpu} can be a negative quantity for a thread
-with a negative @var{nice} value. Negative values of @var{recent_cpu}
-are not changed to 0.
+The value of @var{recent_cpu} can be negative for a thread with a
+negative @var{nice} value. Do not clamp negative @var{recent_cpu} to 0.
You must implement @func{thread_get_recent_cpu}, for which there is a
skeleton in @file{threads/thread.c}.