Long-distance RDMA-acceleration Frameworks
Hitoshi Masutani, Junki Ichikawa, Kiwami Inoue, Tomoya Hibi, Kazuaki Obana, Kugimoto Takeshi, 毅 小倉, Koki Yube, Hirokazu Takahashi, Koichi Takasugi · NTT technical review · 2024
Most datacenter networks have adopted remote direct memory access (RDMA) as the basis of the transport network to their infrastructure because modern RDMA network interface cards can provide high-performance and energy-efficient capabilities to transfer data.Standard RDMA has been developed for short-distance transmission such as internal datacenters for achieving high-performance computing.We are currently developing the Innovative Optical and Wireless Network All-Photonics Network (IOWN APN) to achieve flexible, long-distance and low-latency optical-based networking for newgeneration use cases such as a cyber-physical system.By taking advantage of high-performance and low-latency data transfer in RDMA over long-distance communication such as inter-datacenter networks based on the APN, application-level networking should be accelerated over the IOWN APN.We propose two long-distance RDMA-acceleration frameworks.We first present the RDMA over Open APN framework to increase throughput of RDMA beyond 100 km by using the appropriate queue-pair configuration.This is easy to use without additional components.We then present the RDMA wide area network (WAN) accelerator to build a new long-distance RDMA-transmission framework without resource limitation of SmartNIC in the RDMA over Open APN framework.We also evaluate the performance improvement of the RDMA WAN accelerator compared with standard RDMA.For example, for data transfer of 512-byte messages, the RDMA WAN accelerator has about 35 times performance improvement compared with standard RDMA.