PROPERTIES AND APPLICATIONS OF THE OPTIMAL QUEUING STRATEGY SRPT - A SURVEY

This survey summarizes the results of recent investigations concerning queues operated by the preemptive strategy ''Shortest Remaining Proce ssing Time first'' SRPT. In comparison to the strategies FIFO, LIFO an d PS(Processor Sharing) it is shown for typical traffic conditions tha t the delay time TD of queueing system M/G/1-SRPT is distinguished not only by a low mean value TDBAR but also by a comparably small standar d deviation sigma(D), by a favorable distribution function, F(D)(t) an d a negligible correlation. The SRPT-strategy can be applied to improv e the performance of priority queueing systems and of multi-queue netw orks. Extensive simulation studies have proved that the essential adva ntages of SRPT can be incorporated also in packet-oriented communicati on systems by means of the newly defined combined strategy SRPT/RR and by using the priority mechanisms of standardized network protocols.