基于非易失性存储器的存储系统技术研究进展

 非易失性存储器（NVM）主要包括两类，即适用于外存的、块寻址的闪存和适用于内存的、字节寻址的持久性内存。相比于传统磁盘，闪存具有性能高、能耗低和体积小等优势；相比于DRAM（动态随机存储器），持久性内存如PCM（相变存储器）、RRAM（阻变存储器）等，具有非易失、存储密度高以及同等面积/内存插槽下能给多核环境的CPU 提供更多的数据等优点，这些都为存储系统的高效构建带来了巨大的机遇。然而，传统存储系统的构建方式不适用于非易失性存储器，阻碍了其优势的发挥。为此，分析了基于非易失性存储器构建存储系统的挑战，从闪存、持久性内存两个层次分别综述了它们在存储体系结构、系统软件以及分布式协议方面的变革，总结了基于非易失性存储器构建存储系统的主要研究方向。

Research progress on non-volatile memory based storage system

Non-volatile memory includes both sector-addressable flash memory and byte-addressable persistent memory. Flash memory has advantages like high performance, low energy consumption and light weight compared to hard disk drives, and brings opportunities to high-efficiency storage systems. Byte-addressable persistent memory (e.g., PCM, RRAM etc.)，on the other hand, has high density over volatile DRAM and enlarges the memory space for multi-core CPUs. However, traditional storage systems fail to fully exploit the benefits of the emerging non-volatile memory. This paper first analyzes the challenges of storage system based on nonvolatile memory, and then discusses the revolutions in terms of storage architecture, system software and distributed protocols for flash memory and persistent memory, respectively. Finally, it points out the open problems for future research on storage systems based on the non-volatile memory.