LightRPC: An Efficient and Simple RDMA-based RPC Framework

RDMA has been widely used in modern data centers because it can provide low-latency and high-bandwidth network communication for distributed applications. However, how to build an efficient RDMA-based RPC framework is still challenging. We observe that existing work may have the following problems: First, the lack of a serialization module makes the RPC framework difficult to use, and cannot further be optimized by overlapping serialization and network communication. Second, CPU resources are ignored to scale out instead of focusing on QP and memory resources, which may result in the RPC framework not being scalable. In this paper, we propose LightRPC, which provides users with easy-to-use and portable interfaces via a new resource abstraction and achieves efficient performance through co-design of serialization and communication, usage of pre-registered memory, and adaptive polling mode. Compared to bRPC’s IPoIB and RDMA modes, LightRPC improves throughput by about 2.5x and 1.5x, respectively, and has lower median and tail latency.