lmbench is a micro-benchmark suite designed to focus attention on the basic building blocks of many common system applications, such as databases, simulations, software development, and networking. In almost all cases, the individual tests are the result of analysis and isolation of a customer's actual performance problem. These tools can be, and currently are, used to compare different system implementations from different vendors. The tools have been and continue to be used by processor designers. In several cases, the benchmarks have uncovered previously unknown bugs and design flaws. lmbench includes an extensible database of results from systems current as of late 1995.