Design and Optimization of a Distributed File System Based on RDMA

Abstract

With the rapid development of computer and network technology, to deal with explosively growing mass data correctly, distributed file systems have come into being, and they have been applied in many enterprises. However, in the packet storage process, the traditional TCP/IP transmission protocol has to pass through the operating system and application software layer. It takes up many server resources and memory bus bandwidth, which places a heavy burden on the server’s CPU and memory. In this paper, we analyze the research status of the distributed file system based on analyzing and comparing the advantages of RDMA over traditional TCP Ethernet communication architecture. We propose an optimization scheme for the network transmission performance of the original FastDFS to replace the original TCP module with an RDMA network communication module, and we design a lightweight distributed file system with higher performance than the original FastDFS, which is suitable for small file storage. Using the zero-copy technology and kernel bypass technology of soft RDMA, the network communication mechanism in FastDFS is optimized to free the server’s CPU from heavy data processing work. In this paper, the RDMA-based FastDFS is compared with the original FastDFS. The test results show that the network transmission performance of the optimized FastDFS is improved compared with the original FastDFS, which achieves the expected effect and can better meet the requirements of mass small file storage for today’s Internet applications.

Keywords

• DFS
• RDMA
• kernel-bypass
• zero-copy