Marc Michalke, Francisco Carpio, Admela Jukan

Current serverless solutions are primarily designed to run on cloud centric environments. While bringing these solutions to the edge is its further evolution, it introduces new challenges, due to resource constraints, different CPU architectures, network topology and latency. Specifically, when clustering devices at the edge, inter-node latency plays an important role. In this paper, we experimentally examine the impact that latency has on scalablity by measuring the throughput of distributed serverless applications. We deploy Knative over a Kubernetes cluster of nodes and emulate latencies between them to compare the performance of serverless functions when deployed over centralized versus distributed computing sites. The results show how scaling over edge achieves half the throughput as compared to a centralized deployment in the cloud when the processing times are low, but more than two thirds the improved performance of cloud with increased processing delays.