Ro-RAT系统随机调度算法  

Random I/O Schedule Algorithm for Ro-RAT System

作　　者：康剑斌[1] 汪海山[1] 贾惠波[1] 

机构地区：[1]清华大学精密仪器与机械学系,100084

出　　处：《微计算机信息》2010年第4期4-5,12,共3页Control & Automation

摘　　要：I/O调度对存储系统的性能、响应速度有很大的影响。本文介绍了一种用于地质勘探领域数据存储的Ro-RAT(ReadOnly RAID-tape-library)系统。该系统采用磁盘作为磁带库的缓存系统,以提高整个系统的读取速度。我们设计了一种适合该系统的磁带I/O调度算法SCAN-M。该算法与应用于磁盘I/O调度的电梯算法类似,但针对磁带的特点进行了调度的排序和合并。从仿真结果看,SCAN-M算法对系统的I/O性能有较大的改进。Tape is used widely in high reliability storage system. This paper introduces a storage system named Ro-RAT （Read only RAID-Tape-Library） which can be used in geological exploration storage. Tape is used as storage medium in Ro-RAT. Base on the study of the accessing characteristic, a new I/O schedule algorithm called SCAN-M is introduced. SCAN-M is similar to ＂elevator＂ used widely in disk I/O scheduling, but merges the I/O request in a different way. To evaluate the performance of SCAN-M algorithm, trace-driven simulation experiments were taken. The result shows that SCAN-M can reduce system response time significantly.

关 键 词：I/O调度 磁带 虚拟磁带库 

分 类 号：TP333[自动化与计算机技术—计算机系统结构]