Towards realistic file-system benchmarks with CodeMRI

Abstract

Benchmarks are crucial to understanding software systems and assessing their performance. In file-system research, synthetic benchmarks are accepted and widely used as substitutes for more realistic and complex workloads. However, synthetic benchmarks are largely based on the benchmark writer's interpretation of the real workload, and how it exercises the system API. This is insufficient since even a simple operation through the API may end up exercising the file system in very different ways due to effects of features such as caching and prefetching. In this paper, we describe our first steps in creating "realistic synthetic" benchmarks by building a tool, CodeMRI. CodeMRI leverages file-system domain knowledge and a small amount of system profiling in order to better understand how the benchmark is stressing the system and to deconstruct its workload.