Ratio between average sojourn times under processor sharing and fair sojourn protocol

Under very general assumptions, we prove that the ratio between the average sojourn time in a queue under the processor sharing (PS) and the same queue under the fair sojourn protocol (FSP) can be bounded above, and we derive such a bound in terms of the long-run average system size of the PS queue seen by arrivals. Copyright © 2010 Cambridge University Press.