Rate-function scheduling

Abstract

Rate-Function Scheduling (RFS) is a new deadline-based packet-scheduling service discipline that supports quality-of-service guarantees for applications with real-time communication requirements. RFS is distinguished from other service disciplines in that it achieves all of the following goals: analytically-derived performance bounds, performance isolation among sessions, flexible and efficient allocation of bandwidth, implementation simplicity, work-conserving operation, and bandwidth-fair operation (defined in the paper). Through the specification of rate functions, sessions can control their bandwidth usage and their upper bounds on delay. For a class of rate functions, which we show is sufficient for providing sessions with delay bounds, RFS is as simple to implement and to calculate service bounds such as Zhang's VirtualClock service discipline. We also show that the Non-Preemptive Earliest Deadline First Policy is a simple degeneration of RFS.