RF-RPC: Remote Fetching RPC Paradigm for RDMA-Enabled Network

Remote Direct Memory Access (RDMA) devices are widely deployed in modern data centers. However, existing RDMA usages lead to a dilemma between performance and redesign cost. Server-reply mode directly replaces socket-based send/receive primitives with corresponding RDMA counterparts. It can not fully harness the power of RDMA devices. Server-bypass is distinct mode provided by RDMA for reaching the hardware limits. This mode can totally bypass the server by using one-sided RDMA operations but at the cost of redesigning software. This paper provides a different approach, called RF-RPC (Remote Fetching RPC Paradigm). Different from server-reply, RF-RPC makes client fetch the results from server using one-sided RDMA instead of waiting the results pushed by server. Different from server-bypass, RF-RPC demands server to process client's requests for supporting programming paradigm like RPC. Thus, RF-RPC can achieve high performance without abandoning traditional programming models. An RF-RPC supported in-memory key-value store shows that the performance can be improved by 1.6× comparing to server-reply paradigm and 4× comparing to server-bypass paradigm.