Huge electricity consumption is a severe issue for edge data centers. To this
end, we propose a new form of edge server, namely SoC-Cluster, that
orchestrates many low-power mobile system-on-chips (SoCs) through an on-chip
network. For the first time, we have developed a concrete SoC-Cluster server
that consists of 60 Qualcomm Snapdragon 865 SoCs in a 2U rack. Such a server
has been commercialized successfully and deployed in large scale on edge
clouds. The current dominant workload on those deployed SoC-Clusters is cloud
gaming, as mobile SoCs can seamlessly run native mobile games.
The primary goal of this work is to demystify whether SoC-Cluster can
efficiently serve more general-purpose, edge-typical workloads. Therefore, we
built a benchmark suite that leverages state-of-the-art libraries for two
killer edge workloads, i.e., video transcoding and deep learning inference. The
benchmark comprehensively reports the performance, power consumption, and other
application-specific metrics. We then performed a thorough measurement study
and directly compared SoC-Cluster with traditional edge servers (with Intel CPU
and NVIDIA GPU) with respect to physical size, electricity, and billing. The
results reveal the advantages of SoC-Cluster, especially its high energy
efficiency and the ability to proportionally scale energy consumption with
various incoming loads, as well as its limitations. The results also provide
insightful implications and valuable guidance to further improve SoC-Cluster
and land it in broader edge scenarios