A description language and a tool for identifying, analyzing and addressing performance issues in event traces. With this language, a behavior descriptor may be defined to describe a simple behavior within a performance trace, by specifying values for a relatively small number of attributes. Even a relatively unsophisticated user can define behavior descriptors, but complex behaviors may be defined based on interactions between multiple behavior descriptors. A trace analysis tool may use a library of behavior descriptors to identify performance issues in performance traces by matching behavior descriptors to the performance trace. This analysis may be used in any number of ways, including reporting to a user detected performance issues reflected in a set of performance traces, filtering a set of performance traces to remove those performance traces corresponding to known performance issues or prioritizing efforts to resolve performance issues.