Methods and system described herein are directed to identifying anomalous behaving components of a distributed computing system. Methods and system collect log messages generated by a set of event log source running in the distributed computing system within an observation time window. Frequencies of various types of event messages generated within the observation time window are determined for each of the log sources. A similarity value is calculated for each pair of event sources. The similarity values are used to identify similar clusters of event sources of the distributed computing system for various management purposes. Components of the distributed computing system that are used to host the event source outliers may be identified as potentially having problems or may be an indication of future problems.