The Fine Grained Collaborative NVM File System

The NVM storage device is an effective mean to solve the bottleneck of computer system. However, the high read and write speed of NVM storage devices presents a big challenge to the current file system. In this paper, the kernel and user-space file system for NVM storage devices are analyzed firstly. Then, a new fine grained collaborative NVM file system is designed. The architecture, the collaborative interface and the hybrid I/O request execution strategy are given. It can combine the advantage of the kernel and user-space file system, and retain secure mechanism of OS kernel. The prototype of new fine grained collaborative NVM file system named MLCFS is implemented based on Pmemfile and PMEM. Fio and pjdfstest are used to evaluate and compare with NOVA and Pmemfile. The testing results show that MLCFS can increase the IOPS by 43.2% and 67.3% compared with NOVA and Pmemfile, and reduce the time overhead by 9.5% and 9.1% respectively.