闪存存储系统综述  

Survey on Flash-Based Storage Systems

作　　者：陆游游[1] 舒继武[1,2] 

机构地区：[1]清华大学计算机科学与技术系,北京100084 [2]清华信息科学与技术国家实验室(筹),北京100084

出　　处：《计算机研究与发展》2013年第1期49-59,共11页Journal of Computer Research and Development

基　　金：国家杰出青年科学基金项目(60925006);国家"八六三"高技术研究发展计划基金项目(2012AA011003)

摘　　要：闪存因其低延迟、高并发、低能耗、体积小等特点受到了广泛关注.首先讨论了简单利用闪存固态盘替换传统磁盘的方式隐藏了闪存特性,限制了软件系统对闪存特性充分利用的不足.然后,分析并比较了现有包括闪存加速卡、闪存阵列、基于闪存的分布式集群系统等基于存储介质直接构建的闪存存储系统的特点,归纳了其通过改变硬件接口、调整软件或控制器管理模块、匹配处理器与I/O处理能力等方式实现系统低延迟、高可靠、低能耗等特性的优化方法.然后重点讨论了闪存存储系统3个方面的关键技术:基于I/O栈调整与重构的存储性能优化、系统级可靠性、体积与能耗.最后总结了闪存存储系统的现状与特点,并指出未来可能的研究方向.Flash memory has gained great popularity for its properties of low latency, high parallelism, energy efficient, and small volume. But the direct substitution of flash-based solid state drives for hard disk drives has hidden these properties from the operating system, preventing the operating system from optimizations. In this paper, comparison and analysis are made on the storage systems built on the raw flash, including flash, accelerating cards, flash arrays, and flash-based clusters, which have achieved the goals of low latency, high reliability and energy efficiency through hardware interface change, software or controller module refinement, or computation and I/O capacities matching. Based on the comparison of these recent raw flash based storage systems, challenges and design issues are discussed on three aspects. Firstly, performance optimizations with I/ O stack redesign are surveyed from the hardware interface, notification mechanisms, the system software refinement or redesign, and new storage interfaces for rich semantics. Secondly, the reliability approaches from the system level are described. Finally, the energy efficiency and the volume gains from the flash based storage are presented. After the discussion, the research works are summarized and the possible research directions are pointed out.

关 键 词：闪存 存储系统 I O栈 可靠性 节能 

分 类 号：TP302.1[自动化与计算机技术—计算机系统结构]