A hardware supported method of RDMA transmission for unreliable networks
Longfei Li, HE Zhan-zhuang, Jianfeng Wang, Yangchun Shi · 2017
As to unreliable networks, like Ethernet, waiting for connection establishment can be inefficient during RDMA (Remote Direct Memory Access) transmission. Aiming at solving long waiting problem, a hardware supported RDMA method, DRDMA (Dynamic RDMA), was proposed in this paper. DRDMA, providing a new indirect transmission mode and corresponding dynamic switch policy based on traditional RDMA method, allowed starting RDMA transmission at the same time with connection establishment by sending packages first to indirect buffer in RNIC and copying them later to host memory, which was totally transparent to upper layers. Based on Gigabit Ethernet, we built node models of DRDMA method and set up simulation platforms to perform experiments. Experimental results show that for unreliable networks, DRDMA not only can solve the long waiting problem of connection establishment with little extra hardware cost, but also can provide higher transmission performance compared with traditional RDMA method.