Abstract: An intelligent log file pattern identifier (“pattern identifier”) has been created that intelligently mines log files for patterns in a reduced time complexity of O(N2), which is substantially faster than O(N3). This pattern identifier can leverage truncated hashes of events, a suffix array, and a longest common prefix array to reduce the time complexity of pattern mining from O(N3) to a worst-case time complexity of O(N2). The pattern identifier analyzes event records in a log file using a multi-stage process to perform pattern mining. The multi-stage process involves filtering event records to preserve their static content, performing suffix sorting, and determining common prefix lengths of the suffixes of the static content to determine a full set of non-overlapping patterns across the event records. The pattern identifier then determines and generates a set of unique transaction patterns based on the non-overlapping patterns.