HBench-OS is a suite of portable benchmarks designed to measure the performance of primitive functionality provided by an operating system/hardware platform. HBench-OS was designed primarily as a research tool for the systems research and OS development communities, and thus its major design goal is to provide a flexible system for reproducible, accurate, and statistically-sound performance analysis and evaluation. These characteristics make it ideal for both performance research as well as more traditional consumer-oriented performance measurement and analysis.