Prompting for Automatic Log Template Extraction

Log parsing, the initial and vital stage in automated log analysis, involves extracting log templates from semi-structured logs to generate structured logs. Nonetheless, current log parsers are limited in effectiveness due to two primary reasons. Firstly, traditional data-driven log parsers heavily rely on heuristics or manually crafted features provided by domain experts, which may not consistently yield optimal performance when applied to diverse log systems. Secondly, existing deep learning-based log parsers necessitate model tuning, which is typically confined to training samples and leads to suboptimal performance across the entire log source. To overcome these limitations, we propose a precise log parsing framework named LogDiv, which leverages the in-context inference capability of large language models. Specifically, LogDiv extracts the hidden semantics from multiple log examples through prompt demonstrations. Without the need for model tuning, LogDiv can directly generate a log template for the target log message by leveraging the semantics provided in the prompt context. Additionally, we introduce a simple yet effective prompt format for extracting the output and enhancing the quality of the generated log templates. To validate the performance of LogDiv, we conducted experiments using 16 widely-used public datasets. The results show that LogDiv achieves state-of-the-art performance with an average parsing accuracy of 97.7%, precision template accuracy of 88.1%, and recall template accuracy of 90.8%.