多媒体应用中磁盘阵列读预取Petri网模型及结果分析

RAID Read Pre-Fetch Petri Net Models and Result Analysis in Multimedia Applications

多媒体应用需要大容量、高速磁盘阵列的支持。为了分析采用读预取策略后磁盘阵列的性能,本文建立了读预取Petri网[1]模型。此模型可用以判断系统各环节对读速率的影响和求取读平均数传率。实验表明,采用顺序读预取策略的实际读平均数传率提高了60％,可以满足数字化系统对I/O性能的高要求。

Multimedia applications need large-capacity, high-speed RAIDs ( Redundant Array of Independent Disks) . This paper establishes a read pre-fetch Petri net model in order to analyze the performance of RAIDs which adopts the read prefetch policy. By analyzing this model, we can know each part' s effect on the read performance, and can calculate the average read performance of RAIDs. Tests prove that the average data transfer rate of the RAID which uses the read prefetch policy increases! by 60 % , meeting the high requirement of I/O performance in digital systems.