存储技术必备的方案冗余磁盘阵列

介绍了近年来计算机用于RAID的存储设备接口的发展,陈述了RAID设备应用中应当考虑的因素。     

混合动力汽车故障数据记录系统设计

以某ISG(integrated starter and generater)型混合动力电动汽车为研究对象,开展混合动力电动汽车故障诊断数据记录系统的研究.通过CAN总线和K线的应用,建立混合动力汽车故障诊断信息数据采集的通讯网络.设计了包括CPU处理模块、通信模块、USB存储模块等故障诊断数据记录系统的硬件结构.针对系统要求和特点,在系统硬件方案设计、软件设计的基础上,对USB在系统中实现数据的海量信息存储应用进行了具体的电路设计和分析.在车辆行驶信息记录实验过程中,该故障信息记录系统运行稳定,数据记录完整、准确,在线显示的参数也能较好地反映车辆行驶状态.     

工业监控系统实时数据的Web浏览

为了充分发挥计算机网络的潜能,将Ｉｎｔｅｒｎｅｔ技术与工业现场监控系统结合起来,从而形成一种新的基于浏览器的工业信息监控系统。文章在扬子石化公司贮运厂工业监控系统中运用计算机网络技术、工业监控技术和数据库技术,将工业现场监控系统中各类实时数据、画面、图表等信息接入企业本地的网络服务器中,并以ＨＴＭＬ文本形式进行实时发布,实现工业现场实时数据的Ｗｅｂ 浏览     

光纤磁盘阵列中的流水线技术

根据流水线技术,将光纤通道适配器的数据传输阶段与SCSI适配器的I／O任务执行阶段按流水线技术并行执行,能充分减少系统总的处理时间,提高系统总的数据传输速度．以FC—RAID3000为例,分析了磁盘阵列中I／O流水线技术的适用性与基本原理,介绍了通过设置多进程来并行处理光纤卡和SCSI适配器的数据传输过程,对实现流水线前后的性能进行了测试和比较．经测试发现,阵列系统最大数据传输率与未采用流水线技术的系统相比提高了1倍．     

磁盘阵列cache数据一致性的研究与实现

为了实现磁盘阵列cache数据一致性,采用非易失存储设备NVRAM实现磁盘阵列cache,断电后保持数据不丢失．同时以写事务对cache进行修改,使cache写操作要么全部提交,要么完全撤销,保持cache数据一致性．为了撤销对cache的不完整修改,需要对cache进行备份,使cache能够还原到失败写操作执行之前的状态．若将数据写入cache的空闲块,那么仅需要对cache映射表进行备份;因为当撤销对cache的不完整修改时,将cache映射表的备份对cache映射表赋值,写入部分数据的空闲块还是被cache映射表记为空闲块,cache回到失败的写操作执行之前的状态．试验结果表明：在突然断电或死机情况下,都能确保cache数据的一致性．     

形式化面向对象方法与并发系统的建模

将统一建模语言（UML）的面向对象可视化技术与代数规范语言CafeOBJ的形式描述相结合,对冗余磁盘阵列（RAID）系统中的并发特性进行建模、分析和规范。提供了RAID系统的清晰结构,以此来弥补形式化规范语言的不足,规范软件设计过程,保证程序的正确性。     

TSHOVER:A Novel Coding Scheme for Tolerating Triple Disk Failures in RAID/DRAID

This paper presents a novel method, called TSHOVER, for tolerating up to triple disk failures in RAID/DRAID architectures or others reliable storage systems. TSHOVER is two-dimensional code, which employs horizontal code and vertical code at the same time with simple exclusive-OR (XOR) computations. This paper shows the new step ascending concepts used in encoding, and it has the capability of realizing fault tolerance. TSHOVER has better data recovery ability to those disk network storage systems with relatively more dynamic changes in the number of disks. Compared with RS and STAR code, TSHOVER has better encoding performance. When updating a data strip, only 6 XOR operations are needed. Both experimental results and theoretical analyses show that TSHOVER has better performance and higher efficiency than other algorithms.     

RAID在线数据重建方法仿真器设计

在磁盘系统仿真器DiskSim的基础上,提出了一种独立冗余磁盘阵列在线数据重建方法仿真器的设计方案和实现机制.该仿真器以事件驱动的方式与主磁盘系统仿真器进行信息交互,并支持对2种常用的磁盘阵列重建方法(流水重建方法和面向磁盘的重建方法)的功能和性能仿真.仿真结果证明了磁盘阵列在线数据重建方法仿真器的有效性.     

RDDP: An efficient MDS array code on toleration triple node failures in storage system

It is well known that erasure coding can be used in storage systems to efficiently store data while protecting against failures. Conventionally, the design of erasure codes has focused on the tradeoff between redundancy and reliability. Under this criterion, an maximum distance separable（MDS） code has optimal redundancy. In this paper, we address a new class of MDS array codes for tolerating triple node failures by extending the row di- agonal parity（RDP） code, named the RDDP（row double diagonal parity） code. The RDDP code takes advantages of good perform- ances of the RDP code with balanced I/0. A specific triple-erasure decoding algorithm to reduce decoding complexity is depicted by geometric graph, and it is easily implemented by software and hardware. The theoretical analysis shows that the comprehensive properties of the RDDP code are optimal, such as encoding and decoding efficiency, update efficiency and I/0 balance performance.     

FC-AL远程镜像存储系统设计与实现

提出了一种经济地构建FC AL远程镜像存储网络的方案 ,论述了它的硬件体系结构和存储服务软件体系 .由于利用光纤通道仲裁环结构并结合附网存储的思想 ,该系统具有容量大 ,可扩展性强 ,传输速度快和价格低廉等基本特点     

Design and Implementation of a Fibre Channel Target Driver Supporting SCSI

Fibre channel storage area networks (FC-SAN) are effective solutions to address storage management problems caused by very large volumes of data. But the expense of fibre channel devices limits FC-SAN applications. The use of IP networks instead of fibre channel networks will reduce SAN cost, but will also reduce the performance. Therefore, small computer system interface (SCSI) devices were considered to replace FC disks to reduce the SAN cost. A driver for the FC network adapter and the FC target, designed and implemented to support this structure, obeys the SCSI protocol and works in target mode with 200 MB/s bandwidth. The FC target architecture and implementation were compared with the FC initiator.The SCSI command transfer process in the FC layer was described. The performance test results show that the maximum I/O throughput reachs 167 MB/s for read requests and 196 MB/s for write requests (FC bandwidth is 200 MB/s), verifying that the FC target is very efficient. The modularization, efficiency, and low cost of the FC target will enable SAN and fibre channel to be more widely used in applications.     

线控转向汽车横摆角速度增益优化设计

为了解决汽车线控转向系统(SBW)转向角传动比的设计问题,对SBW汽车横摆角速度增益值优化方法进行了研究。在建立整车动力学模型和驾驶员模型的基础上,从人-车闭环系统角度出发,采用汽车操纵稳定性综合评价体系中的轨迹跟踪误差评价指标、驾驶员操纵负担的评价指标、侧翻危险性评价指标和侧滑危险性评价指标并与遗传算法相结合,在典型车速下对汽车横摆角速度增益值进行了优化。试验结果表明,采用优化后横摆角速度增益值设计的SBW转向传动比可有效地提高汽车操纵性,减轻驾驶员负担。