Edge computing has emerged as a popular paradigm for running latency-sensitive applications due to its ability to offer lower network latencies to end-users. In this paper, we argue that despite its lower network latency, the resource-constrained nature of the edge can result in higher end-to-end latency, especially at higher utilizations, when compared to cloud data centers. We study this edge performance inversion problem through an analytic comparison of edge and cloud latencies and analyze conditions under which the edge can yield worse performance than the cloud. To verify our analytic results, we conduct a detailed experimental comparison of the edge and the cloud latencies using a realistic application and real cloud workloads. Both our analytical and experimental results show that even at moderate utilizations, the edge queuing delays can offset the benefits of lower network latencies, and even result in performance inversion where running in the cloud would provide superior latencies. We finally discuss practical implications of our results and provide insights into how application designers and service providers should design edge applications and systems to avoid these pitfalls.
翻译:电磁计算由于能够向终端用户提供较低的网络延迟时间而成为运行对潜伏敏感应用的流行范例。 在本文中,我们争论说,尽管其网络延迟时间较低,但边缘资源紧张的性质可能导致终端到终端的延迟时间较高,特别是在与云数据中心相比使用率较高的情况下。我们通过对边缘和云层晚期的分析性比较来研究这种边缘性能倒置问题,并分析边缘性能比云层更差的条件。为了核实我们的分析结果,我们利用现实的应用和实际的云层工作量,对边缘和云层延迟进行详细的实验性比较。我们的分析和实验结果都表明,即便在适度使用时,边缘性排卵延迟也能够抵消网络延迟时间较低的好处,甚至导致在云层运行时的反向性能,从而提供超常的延迟时间。我们最后讨论我们结果的实际影响,并深入了解应用设计师和服务提供者如何设计边缘性应用程序和系统以避免这些缺陷。