The Response Times of Priority Classes under Preemptive Resume in M/M/m Queues

Expressions are derived for the mean response times of each priority level in a multiserver M / M / m queue operating under preemptive resume scheduling. Exact results are obtained for cases where all priorities have the same mean service times; approximate results are obtained for the more general case where mean service times may differ. The results hold for any number of servers and any number of classes. For each priority level, it is assumed that arrivals are Poisson and service times are exponentially distributed.