Time-Sensitive Networking (TSN) has been recognized as one of the key enabling technologies for Industry 4.0 and has been deployed in many time- and mission-critical industrial applications, e.g., automotive and aerospace systems. Given the stringent real-time communication requirements raised by these applications, the Time-Aware Shaper (TAS) draws special attention among the many traffic shapers developed for TSN, due to its ability to achieve deterministic latency guarantees. Extensive efforts on the designs of scheduling methods for TAS shapers have been reported in recent years to improve the system schedulability, each with their own distinct focuses and concerns. However, these scheduling methods have yet to be thoroughly evaluated, especially through experimental comparisons, to provide a systematical understanding on their performance using different evaluation metrics in various application scenarios. In this paper, we fill this gap by presenting a comprehensive experimental study on the existing TAS-based scheduling methods for TSN. We first categorize the system models employed in these work along with their formulated problems, and outline the fundamental considerations in the designs of TAS-based scheduling methods. We then perform extensive evaluation on 16 representative solutions and compare their performance under both synthetic scenarios and real-life industrial use cases. Through these experimental studies, we identify the limitations of individual scheduling methods and highlight several important findings. This work will provide foundational knowledge for the future studies on TSN real-time scheduling problems, and serve as the performance benchmarking for scheduling method development in TSN.

翻译：时间敏感网络（TSN）已被公认为工业4.0的关键使能技术之一，并已部署于众多时间关键与任务关键型工业应用（如汽车与航空航天系统）中。针对这些应用提出的严苛实时通信需求，TSN所开发的多种流量整形器中，时间感知整形器（TAS）因其实现确定性延迟保障的能力而备受关注。近年来，针对TAS整形的调度方法设计已涌现大量研究工作以提升系统可调度性，各项研究各有侧重与关注点。然而，这些调度方法尚未得到充分评估，特别是缺乏实验比较，以系统性地理解其在不同应用场景下采用不同评估指标的性能表现。本文通过开展全面的实验研究填补了这一空白：首先对现有TAS调度方法所采用的系统模型及其形式化问题进行分类，并概述TAS调度方法设计中的基本考量；随后对16种代表性方案进行广泛评估，比较其在合成场景与真实工业用例下的性能。通过这些实验研究，我们识别出各调度方法的局限性，并提炼出若干重要发现。本工作将为未来TSN实时调度问题的研究提供基础理论支撑，并为TSN调度方法开发提供性能基准参照。