A method, an electronic device, and a computer program product for obtaining a hierarchical data structure and processing a log entry is disclosed. The method for obtaining the hierarchical data structure includes: obtaining corresponding characteristic information included in each log entry of a set of log entries and determining multiple log entry patterns based on the corresponding characteristic information. The pattern characteristic information of each log entry pattern corresponds to the characteristic information of a subset of log entries in the set of log entries. The method also includes storing the set of log entries according to the hierarchical data structure so that each log entry is associated with at least one of multiple nodes of the hierarchical data structure. The multiple nodes respectively correspond to the multiple log entry patterns, and are hierarchically organized based on respective corresponding log entry patterns.