固态硬盘中的写放大系数分析  

Analysis of write amplification phenomenon in solid-state hard disks

作　　者：王伟能[1] 马建设[1] 倪凯[1] 潘龙法[1] 赵懿[1] 王仲超 王鸿钧[1] 

机构地区：[1]清华大学光盘国家工程研究中心深圳分中心

出　　处：《记录媒体技术》2010年第2期26-28,共3页China Mediatech

摘　　要：目前采用的带有机械式磁头读写的磁存储硬盘,在速度、可靠性等方面已经越来越不适应现在的需要,因碰存储硬盘可靠性导致的数据安全问题日益严重。而以闪存为存储介质的固态硬盘具有读写速度快、易扩展、功耗小、噪声低等优点,尤其能够在恶劣的环境下正常工作,可靠性高,正好弥补了常规硬盘的这一缺陷,因此成为了现阶段的研究热点。由于闪存存储介质具有"写先擦除"特性,所以会导致固态硬盘的写放大现象出现。本文介绍了固态硬盘中的写放大现象,分析了影响写放大系数大小的因素,得到了有效抑制写放大系数的方法——固态硬盘的备用存储系数越大,写放大系数越小,为固态硬盘管理策略及算法设计提供了指导意见。Currently used magnetic storage hard disks,with Mechanical heads to read and write, become increasingly unsuited to the present needs in terms of speed,reliability and so on,and because of the reliability of magnetic storage hard disks the problems of data security issues become serious. Flash-based solid state disks having advantages of high speed of reading and writing,easy to expand, low power consumption,low noise,be able to work in harsh environment and high reliability,which overcome shortcomings of conventional hard disks,are becoming the current focus of research.As the flash memory storage media has'erase-before-write'feature,it will lead to write amplification phenomenon of solid-state hard disks. This paper describes write amplification phenomenon of solid-state hard drives,analysis of impact factors of the size of write amplification factor,gets the method of suppressing the write amplification factor- the larger the spare factor of solid state hard drives,the smaller the write amplification factor, and provides guidance for design management strategies and algorithms of solid state drives.

关 键 词：固态硬盘 存储介质 读写速度 磁存储 系数分析 数据安全 算法设计 垃圾回收 用户空间 重定向 

分 类 号：TP333.35[自动化与计算机技术—计算机系统结构]