vBench: A micro-benchmark for File - I/O performance of virtual machines

Resurgence of virtualization calls for suitable benchmark to validate the design of virtualization system. Among the virtual machines' performance, I/O especially disk I/O is the most critical one. Since I/O is a key factor that impacts virtual machine performance, this paper introduces a benchmark- vBench for disk I/O micro-performance evaluation of virtual machine. vBench is mainly consisted of serial disk I/O evaluation and parallel disk I/O evaluation. Since error during test is inevitable, for the purpose of error correction, we design an efficient approach which we runs the same workloads in two loops, then the execution times of two loops minus each other. The approach can correctly deal with loop overhead. To prevent compiler from optimizing the code and lead to the wrong execution time of workloads, vBench is embedded inline assembly code. vBench provides the performance evaluation for system call of disk I/O, application level disk I/O and parallel disk I/O. Disk I/O performance evaluation of vBench can measure disk I/O micro-performance of virtual machine in certain extreme conditions. Experiments show that the results of vBench are accurate and vBench can reflect the disk I/O performance of the virtual machines correctly. Therefore, vBench is more accurate, more reliable than the traditional benchmarks and more suitable for evaluating virtual machine disk I/O performance.