Logging is a universal approach to recording important events in system workflows of distributed systems. Current log analysis tools ignore the semantic knowledge that is key to workflow construction and analysis. In addition, they focus on infrastructure-level distributed systems. Because of fundamental differences in log features, they are ineffective in distributed data analytics systems. This paper proposes IntelLog, a semantic-aware non-intrusive workflow reconstruction tool for distributed data analytics systems. It is capable of building hierarchical relationships between components and events from logs generated by the targeted systems with little or even no domain knowledge. Leveraging natural language processing, IntelLog automatically extracts and formats semantic information in each log message, including system events, identifiers, locality information, and metrics values. It builds a graph to represent the hierarchical relationship of components in the targeted system via nomenclature conventions. We implement IntelLog for Hadoop MapReduce, Spark and Tez. Evaluation results show that IntelLog provides a fine-grained view of the system workflows with semantics. It outperforms existing tools in automatically detecting anomalies caused by real-world problems, misconfigurations and system bugs. Users can query the formatted semantic knowledge to understand and further troubleshoot the systems.
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It Can Understand the Logs, Literally
Workflow reconstruction through logs is crucial for troubleshooting targeted distributed systems. It is also challenging to extract enough information from logs and keep a concise view, which makes manual log analysis hard to practice. However, currently popular tools rely on identifier-based log parsing, leaving a large amount of workflow information unexploited. In this paper, we propose a log extraction approach NLog, which utilizes a natural language processing based approach to obtain the key information from log messages and identify the same object in logs generated by different statements without any domain knowledge. We propose to use keyed message, a new log storage structure to store the parsed logs. We implement NLog and apply it to distributed data analytics frameworks Spark and MapReduce. Evaluation results show that NLog can accurately identify the objects in log messages even without explicit identifiers. By using keyed messages, users can have a concise as well as flexible view of the workflows.
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- Award ID(s):
- 1816850
- PAR ID:
- 10142541
- Date Published:
- Journal Name:
- 2019 IEEE International Parallel and Distributed Processing Symposium Workshops (IPDPSW)
- Page Range / eLocation ID:
- 446 to 451
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Logging is a universal approach to recording important events in system workflows of distributed systems. Current log analysis tools ignore the semantic knowledge that is key to workflow construction and analysis. In addition, they focus on infrastructure-level distributed systems. Because of fundamental differences in log features, they are ineffective in distributed data analytics systems. This paper proposes IntelLog, a semantic-aware non-intrusive workflow reconstruction tool for distributed data analytics systems. It is capable of building hierarchical relationships between components and events from logs generated by the targeted systems with little or even no domain knowledge. Leveraging natural language processing, IntelLog automatically extracts and formats semantic information in each log message, including system events, identifiers, locality information, and metrics values. It builds a graph to represent the hierarchical relationship of components in the targeted system via nomenclature conventions. We implement IntelLog for Hadoop MapReduce, Spark and Tez. Evaluation results show that IntelLog provides a fine-grained view of the system workflows with semantics. It outperforms existing tools in automatically detecting anomalies caused by real-world problems, misconfigurations and system bugs. Users can query the formatted semantic knowledge to understand and further troubleshoot the systems.more » « less
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