An Anomaly Detection Approach of Part-of-Speech Log Sequence via Population Based Training

Log data is a valuable resource for understanding system status. Log recording running status for a computer system is commonly used to identify performance issues and malfunctions. Sequential anomaly detection of logs is crucial for building a secure and stable system and is beneficial for the discovery, location, and analysis of system failures. In this paper, we propose a new log sequential anomaly detection method based on natural language processing techniques by the Population Based Training (PBT) algorithm, which can make full use of semantic information in log templates to analyze log sequences. The Part-of-Speech (PoS) weight mechanism is first employed to improve the digital representation quality of the log template in the feature extraction. And then, TextCNN is used to extract noteworthy information in log template vectors. In the sequence log anomaly detection stage, the combination of TextCNN and LSTM neural network can improve the accuracy of log sequential anomaly detection. On the other hand, the proposed method jointly trains the parameters of the PoS weight mechanism and the parameters of the anomaly detection neural network model through the PBT algorithm, which accelerates the model convergence speed and improves the accuracy of the log sequential anomaly detection. Our model has been tested on four data sets and compared with two state-of-the-art models to prove the effectiveness of our model. The experimental results show that, compared with other log anomaly detection methods, the proposed method performs well.