基于eMMC存储系统性能的研究与优化

发布时间：2018-03-18 19:58

本文选题：存储系统　切入点：嵌入式平台　出处：《北京邮电大学》2012年硕士论文　论文类型：学位论文

【摘要】：在手机市场,从2009年开始,智能型手机内嵌风潮涌起,随着智能手机的普及,eMMC(embedded Multimedia Card)作为主流的嵌入式存储器,它的使用将更加广泛。但是由于受eMMC设备自身特性的影响,基于eMMC的存储系统面临的问题多种多样,如不同厂家的设备读写性能相差较大；随机读写性能不稳定,尤其是小数据的随机写性能表现较差；设备的使用寿命不稳定等,所以迫切需要我们对嵌入式存储系统性能进行优化,以便提高智能型手机存储系统的性能。目前,虽然对该存储系统性能的优化没有统一的标准,但是目的都是明确的,那就是尽可能快的满足用户的读写请求。本论文首先对块设备驱动程序的实现原理与工作流程进行了介绍,然后分析了eMMC设备本身的特性,研究了eMMC设备的驱动程序的主要功能模块,并在原有驱动程序的基础上,引入三个新的驱动程序功能模块,即快速擦除、高优先级中断、后台处理,在一定程度上提高了系统的I/O(输入输出)性能,延长了eMMC设备的使用寿命。本文还对嵌入式Linux系统中I/0调度算法进行分析研究,基于I/0调度程序设计并实现了一种软件方案Flashfast,该方案在一定程度上提高了小数据块的随机写性能。最后本论文使用特定的测试工具对优化后的系统进行实际的读写测试,并得出了预期的结果。
[Abstract]:In the mobile phone market, since 2009, there has been a surge of embedded Multimedia cards in smart phones. With the popularity of smart phones, embedded Multimedia cards will be used more widely as mainstream embedded memory. However, due to the influence of the characteristics of eMMC devices, The storage system based on eMMC has a variety of problems, such as the large difference in read and write performance of devices from different manufacturers, the instability of random reading and writing performance, especially the poor performance of random write performance of small data, the unstable service life of devices, etc. So we urgently need to optimize the performance of embedded storage system in order to improve the performance of smart phone storage system. That is to meet the user's read and write requests as quickly as possible. This paper first introduces the principle and workflow of the block device driver, then analyzes the characteristics of the eMMC device itself, studies the main function modules of the eMMC device driver, and on the basis of the original driver program. The introduction of three new driver function modules, namely, fast erasure, high priority interrupt, background processing, improves the I / O (I / O) performance of the system to a certain extent. The service life of eMMC equipment is prolonged. In this paper, I / 0 scheduling algorithm in embedded Linux system is analyzed and studied. Based on I / 0 scheduler, a software scheme Flash fastis designed and implemented, which improves the random write performance of small data blocks to a certain extent. Finally, this paper uses specific testing tools to test the optimized system. The expected results are obtained.
【学位授予单位】：北京邮电大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TP333

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