An application performance management system is provided, which is adapted to analyze the performance of one or more applications running on information technology (IT) infrastructure. The application performance management system includes a data collector, an anomaly detector, an anomaly correlator, an anomaly ranking unit, and a source problem detector. The data collector collects performance metrics for one or more applications running on the IT infrastructure. The anomaly detector analyzes the performance metrics and detects anomalies, which may include performance metrics whose values deviate from historic values with a deviation that exceeds a predefined threshold. The anomaly correlator detects dependencies between plural anomalies and generates anomaly clusters. Each anomaly cluster includes anomalies that are correlated through one or more of the dependencies. The anomaly ranking unit ranks anomalies within an anomaly cluster. The source problem detector pinpoints a problem source from the lowest ranked anomaly in an anomaly cluster.