Component-based enterprise systems often suffer from performance issues as a result of poor system design. In this paper, we propose a framework to automatically detect, assess and visualize poor system design, from a performance perspective, by analyzing run-time data using data mining techniques. Categories and Subject Descriptors D.2.2 [Software Engineering]: Design Tools and Techniques – Computer-aided software engineering (CASE). General Terms Measurement, Performance, Design. Keywords Enterprise Java Beans (EJB), Component-Based Systems (CBS), Data Mining, Dynamic Analysis, Antipatterns.