Scheduling for Periodic Multi-Source Systems with Peak-Age Violation Guarantees

TL;DR

This paper investigates scheduling policies for multi-source systems to ensure peak-age violation guarantees, analyzing the decay rate of age violation probability under different queueing disciplines and proposing a generalized round-robin policy.

Contribution

It introduces a generalized round-robin scheduling policy for heterogeneous sources and provides rigorous bounds on age violation probability decay rates for different queueing disciplines.

Findings

GRR scheduling effectively serves multiple sources with heterogeneous arrivals.

Bounds accurately capture the decay rate of age violation probability.

Single packet discipline outperforms infinite queue discipline in homogeneous settings.

Abstract

Age of information (AoI) is an effective performance metric measuring the freshness of information and is particularly suitable for applications involving status update. In this paper, using the age violation probability as the metric, scheduling for heterogeneous multi-source systems is studied. Two queueing disciplines, namely the infinite packet queueing discipline and the single packet queueing discipline, are considered for scheduling packets within each source. A generalized round-robin (GRR) scheduling policy is then proposed to schedule the sources. Bounds on the exponential decay rate of the age violation probability for the proposed GRR scheduling policy under each queueing discipline are rigorously analyzed. Simulation results are provided, which show that the proposed GRR scheduling policy can efficiently serve many sources with heterogeneous arrivals and that our bounds can capture the true decay rate quite accurately. When specialized to the homogeneous source setting, the analysis concretizes the common belief that the single packet queueing discipline has a better AoI performance than the infinite packet queueing discipline. Moreover, simulations on this special case reveals that under the proposed scheduling policy, the two disciplines would have similar asymptotic performance when the inter-arrival time is much larger than the total transmission time.