Energy-Efficient KBP: Kernel Enhancements for Low-Latency and Energy-Efficient Networking

Abstract

Real-time applications are becoming more and more practical, and due to the needs for miniaturized and portable user devices, offloading terminal processing to edge servers is being considered. Additionally, it is necessary to process packets with low latency on edge servers, which are often virtualized for operability. When trying to achieve low-latency networking, the increase in server power consumption due to performance tuning and busy polling for fast packet receiving becomes a problem. Thus, we designed and implemented a low-latency and energy-efficient networking system, energy-efficient kernel busy poll (EE-KBP), which meets four requirements: (A) low latency in the order of microseconds for packet forwarding in a virtual server, (B) lower power consumption than existing solutions, (C) no need for application modification, and (D) no need for software redevelopment for each kernel security update. This EE-KBP has a polling thread in a Linux kernel that receives packets with low latency in polling mode while packets are arriving, and when no packets are arriving, it sleeps and controls the CPU operating frequency low. Evaluation results indicated that EE-KBP achieved microsecond-order low-latency networking under most traffic conditions, and achieved 1.4 × to 3.1 × higher throughput and consumed lower power than NAPI used in a Linux kernel.