GPS scheduling with graceful rate adaptation

This paper addresses a shortcoming of the widely used generalized processor sharing (GPS) scheduling algorithm which can have significant impact on the provided service, however which has been given little attention. Since, with GPS, the service rate received by a session is proportional to the number of backlogged sessions in the system, the service rate of a session may change abruptly if some other session becomes active. This may result in abrupt increases of delay of consecutive packets. W present and analyze a new scheduler, called slow-start GPS (S/sup 2/GPS), which alleviates the problem. S/sup 2/GPS is a modification of GPS where a session does not receive its guaranteed service rate immediately after it be comes active. Instead, the service rate of a session is gradually increased.