Throughput Fairness Round Robin Scheduler for Non-Continuous Flows

Abstract

A queue scheduling algorithm TFRR (throughput fairness round robin) is proposed and studied. TFRR provides better long-term fairness in case of the existence of non-continuous packet flows. Merit and deficiency of the classical fair queue algorithm DRR are studied. The phenomenon that there always exist some non-continuous flows is disclosed. TFRR is constructed based on DRR. Firstly TFRR guarantee the basic bandwidth need of all flows just like DRR. Then the surplus bandwidth is distributed to the flows that have lost bandwidth in the early non-continuous periods, to provide better long-term fairness with complexity of O(1). The improvement of the long-term fairness of TFRR, compared with DRR, is proved by inference and simulation.