Research And Implementation Of Distributed I/O Trace Collection And Replay Technology

Storage performance evaluation technology plays an irreplaceable role in the researchof information storage technology. However, the current storage performance evaluationtechnology does not fully consider about the real application environment, which resultingin less reference value of the evaluation consequence. Aim at this kind of situation, thispaper researches evaluation technology on performance of storage based on realapplication environments, designs and implements a distributed I/O trace collection andreplay system. The system can test the support and performance of a storage system invarious real application environments via reproducing the real application environmentson it.First, in-depth research on trace collection technology. By means of analyzing of I/Orequests of applications from file level and block level, this paper designs the formats offile level trace and block level trace. Research capture technology of I/O trace based onLinux kernel. The capture technology of file level trace and block level trace are based onvirtual file system and blktrace of Linux kernel respectively. The trace collection moduleuses buffer pool technology to minimize the impact on the target system, and has featuressuch as lightweight and dynamic loading.Second, research technology of I/O trace replay to reproduce the applicationenvironment according to the I/O trace. By analyzing the process of trace replay, design akind of strategy of replay, which allows users to adjust the time scale, hence it can meetvarious test requirements and shorten test time. The trace replay module supports opentrace format, and therefore increases the scalability of the system and enriches tracesources.Then, design and implement a distributed control platform. This platform provides auser interface, via which users can control several test nodes to start I/O trace collection orreplay at the same time, and function of centralized trace resource management. Finally, do a number of tests on the distributed I/O trace collection and replay system.Test modules mainly includes file level trace collection module, block level tracecollection module, file level trace replay module, block level trace replay module andopen trace importing and exporting module. Verify the reasonableness of the overallsystem design and the accuracy of achieve through analyzing and comparison of testresults.