一种基于虚拟机的高效磁盘I/O特征分析方法

于磁盘系统的机械运动本质,磁盘系统I/O往往会成为计算机系统的性能瓶颈.为了有效地提高系统性能,收集和分析应用系统的磁盘I/O特征信息将成为性能优化工作的重要基础.与以往I/O特征分析方法不同,给出了一种基于Xen 3.0虚拟机系统的磁盘I/O特征在线分析方法.在虚拟机环境下,该磁盘I/O特征采集方法可以透明地应用于任意无须修改的操作系统.该方法可以高效地在线采集多种基本I/O特征数据,其中包括:磁盘I/O块大小、I/O延迟、I/O时间间隔、I/O空间局部性、时间局部性以及磁盘I/O操作热点分布.通过测试和分析,该在线I/O分析方法有着较小的系统开销,并且对应用系统I/O性能的影响很小.此外,还给出了在大文件拷贝、基于Filebench的filemirco和varmail等工作负载下的I/O特征分析结果.

Efficient Disk I/O Characteristics Analysis Method Based on Virtual Machine Technology

Disk I/O may be the bottleneck in computer systems because of the mechanism characters in disk system. In order to tune the system performance effectively, the collection of the disk I/O workload characteristics will be the essential step for the performance optimization. Compared with other I/O characteristics collection methods, this paper presents an on-line I/O characteristics analysis method based on Xen 3.0 virtual machine system. In virtual machine environments, this method can be transparent to the unmodified operating system. With this method, several essential I/O characteristics metrics can be collected, such as disk I/O block size, I/O latency, I/O arrival interval, I/O spatial locality statistics, I/O time locality statistics and the I/O operation hotspot distribution. Through the testing and analysis, this method is found to have little system overhead and impact on the application system I/O performance. In addition, the I/O characteristics analysis results are demonstrated on the large file copy workload and the Filebench benchmark workload generated by the filemicro and varmail personalities.