Abstract: I/O system software stack is an important factor that affects the efficiency of NVM (Non-Volatile Memory) storage system. For NVM storage systems with unbalanced read/write speeds and limited writing lifetimes, new synchronous and asynchronous converged access management strategy was designed. While an asynchronous write cache was implemented by DRAM for the write access to large data, synchronous management strategy was still used for the read access and the write access to small data. Addressing large time overhead of address translation for NVM storage systems by conflict among cores in a computer with multi-core processor, a new address translation cache was designed for multi-core processor to reduce time overhead of address translation. Finally, a prototype of Concurrent NVM Storage system (CNVMS) was implemented, and the universal testing tools were used to test performance of random reads writes, sequential reads writes, mixed reads/writes and with actual application workload. The experimental results show that the proposed strategy increases read and write speed by 1%-22% and IOPS (Input/Output operations Per Second) by 9%-15% compared with PMBD (Persistent Memory Block Driver), which verifies that CNVMS strategy can provide higher I/O performance and better access request processing speed.

Key words: Non-Volatile Memory (NVM), storage system, I/O system software stack

摘要： I/O系统软件栈是影响NVM存储系统性能的重要因素。针对NVM存储系统的读写速度不均衡、写寿命有限等问题，设计了同异步融合的访问请求管理策略；在使用异步策略管理数据量较大的写操作的同时，仍然使用同步策略管理读请求和少量数据的写请求。针对多核处理器环境下不同计算核心访问存储系统时地址转换开销大的问题，设计了面向多核处理器地址转换缓存策略，减少地址转换的时间开销。最后实现了支持高并发访问NVM存储系统（CNVMS）的原型，并使用通用测试工具进行了随机读写、顺序读写、混合读写和实际应用负载的测试。实验结果表明，与PMBD相比，所提策略能提高1%~22%的读写速度和9%~15%的IOPS，验证了CNVMS策略能有效提高NVM存储系统的I/O性能和访问请求处理速度。

关键词: NVM, 存储系统, I/O系统软件栈