A High Throughput NVM Storage System Based on Access Request Conflict Detection

The NVM storage is a useful way to improve the efficiency of storage system in computer. However, there is a lack of adaptation and optimization mechanisms for NVM storage devices in I/O stack of operating system. Especially, the file system-based lock mechanism becomes an important factor affecting the efficiency of NVM storage systems. In this paper, we embed the management function of the access request for storage system in the NVM storage device. In order to improve the access request concurrency of operating system and alleviate the performance bottleneck caused by the device interface, we remove the existing lock mechanism in file system and use the conflict detection algorithm in NVM storage devices. Firstly, the structure of the high-throughput NVM storage system is given. Then, an access request management method based on two-dimensional linked list is design to change the structure of access request management and reduce the conflict of management. And a conflict detection algorithm is design to manage the access requests for the sharing data stored in NVM storage device. The new submission and release process for access requests are designed. Finally, the prototype of high throughput NVM storage system named HTPM is implemented based on PMEM, which is the open source NVM storage device simulator from Intel. The I/O performance and throughput of HTPM are tested by Fio and Filebench. The results show that HTPM can improve the IOPS by 31.9% and the I/O performance by 21.4% compared with PMEM.