一句话:融合 trace、日志与指标的多模态数据,通过因果图与奖励机制将微服务根因定位细化到指标级。
大规模微服务系统复杂且动态,人工排障耗时且不现实,自动根因分析(RCA)因而至关重要。现有方法存在三点不足:多依赖单一数据源(trace、日志或指标),无法全面刻画系统状态;忽略服务的异常状态与异常强度;服务级定位粒度过粗,难以支撑快速修复。为此,作者提出 MRCA,一种基于多模态数据的指标级 RCA 方法,其核心洞察是多模态数据可带来对系统的整体理解,从而覆盖更多异常场景。MRCA 先利用 trace 与日志、基于重构概率得到异常服务排序,再从高异常概率服务出发构建因果图,发现不同服务异常指标的发生顺序;通过引入奖励机制及时终止因果图的过度扩张,显著缩短因果分析耗时;最后依据因果图对排序列表剪枝,识别指标级根因。在两个常用微服务基准上的实验表明,MRCA 在准确率与效率上均优于现有最佳方法。
Due to the complexity and dynamic nature of large-scale microservice systems, manual troubleshooting is time-consuming and impractical. Therefore, automated Root Cause Analysis (RCA) is essential. However, existing RCA approaches face significant challenges. (1) Multi-modal data (e.g. traces, logs, and metrics) record the status of microservice systems, but most existing RCA approaches rely on single-source data, failing to understand the system fully. (2) Existing RCA approaches ignore the services’ anomaly state and their anomaly intensity. (3) The service-level RCAs lack detailed information for quick issue resolution. To tackle these challenges, we propose MRCA, a metric-level RCA approach using multi-modal data. Our key insight is that using multi-modal data allows for a comprehensive understanding of the system, enabling the localization of root causes across more anomaly scenarios. MRCA first utilizes traces and logs to obtain the ranking list of abnormal services based on reconstruction probability. It further builds causal graphs from services with high anomaly probability to discover the order in which abnormal metrics of different services occur. By incorporating a reward mechanism, MRCA terminates the excessive expansion of the causal graph and significantly reduces the time taken for causal analysis. Finally, MRCA can prune the ranking list based on the causal graph and identify metric-level root causes. Experiments on two widely-used microservice benchmarks demonstrate that MRCA outperforms state-of-the-art approaches in terms of both accuracy and efficiency.