一种高可用对象存储系统的数据组织研究  

Data Organization Research of the High Availability Object Storage System

作　　者：詹玲[1] 张强善[2,3] 万继光[1] 

机构地区：[1]华中科技大学计算机学院信息存储系统教育部重点实验室武汉光电国家实验室,武汉430074 [2]武汉大学计算机学院,武汉430072 [3]信阳职业技术学院网络中心,信阳464000

出　　处：《计算机科学》2009年第11期123-126,130,共5页Computer Science

基　　金：国家自然科学基金重点项目(编号:60933002);国家863计划重大项目(编号:2009AA01A402)资助

摘　　要：通过对现有不同存储系统的容错能力进行认真分析,提出了一种新的高可用对象存储系统架构HAOSS(High Availability Object Storage System)。HAOSS系统分两层:上层存储的对象采用在多个设备之间的数据备份的方式来实现高可靠性,多个备份能够同时对外提供服务,保证系统的高性能,但是磁盘利用率比较低。下层采用RAID5,RAID6以及RAID_Blaum等不同的容错编码来实现多盘容错功能,磁盘利用率较高,但是由于编码越来越复杂,容错编码需要大量的计算,性能受到很大的影响。在数据组织上,新对象和热点对象放上层,这样大部分请求都能够在上层命中,从而保证系统的性能。下层主要用来放不常用的数据,磁盘利用率比较高。在1000Mbps以太网环境下对HAOSS性能进行了测试,结果表明,HAOSS顺序读写性能都比较好,最大可以达到104MB/s,达到1000Mb以太网的理论最大物理带宽。Based on a thorough analysis on the fault-tolerance capability on various existing storage systems, we proposed a new hierarchical, highly reliable, multi-disk fault-tolerant storage system architecture： High Availability Object Stora-ge System （HAOSS）. The HAOSS is composed of two layers： the upper-layer and the lower-layer. The upper-layer achieves the high availability by storing multiple replicas for each storage object in a set of storage devices. The individual replicas can service the I/O requests in parallel so as to obtain high performance. But the effective disk space utilization rate for the upper-layer is relatively low. The lower-layer deploys RAIDS, RAID6 or RAID_Blaum coding schemes to tolerate multi-disk failures. The disk utilization rate of coding schemes is higher than that of multiple replicas. These advantages come at the price of more complicated fault-tolerant coding schemes, which involve a large amount of calculation for encoding and cause an adverse impact on the I/O performance. The HAOSS puts new objects and hot objects in its upper-layer, so that the majority of the requests are absorbed by the upper-layer, hence achieving guaranteed system I/O performance. The main purpose of the lower-layer is to provide a reservoir for the cold data. In a 1000Mb Ethernet interconnection environment, with a request block size of 1024kB, the sequential read performance for a HAOSS server reaches 104MB/s, which is very close to the theoretical maximum effective bandwidth of Ethernet networks.

关 键 词：数据组织 高可用 对象存储 容错 

分 类 号：TP303[自动化与计算机技术—计算机系统结构]