We present Roots, a full-stack monitoring and analysis system for performance anomaly detection and bottleneck identification in cloud platform-as-a-service (PaaS) systems. Roots facilitates application performance monitoring as a core capability of PaaS clouds, and relieves the developers from having to instrument application code. Roots tracks HTTP/S requests to hosted cloud applications and their use of PaaS services. To do so it employs lightweight monitoring of PaaS service interfaces. Roots processes this data in the background using multiple statistical techniques that in combination detect performance anomalies (i.e., violations of service-level objectives). For each anomaly, Roots determines whether the event was caused by a change in the request workload or by a performance bottleneck in a PaaS service. By correlating data collected across different layers of the PaaS, Roots is able to trace high-level performance anomalies to bottlenecks in specific components in the cloud platform. We implement Roots using the AppScale PaaS and evaluate its overhead and accuracy.

中文翻译：

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检测云平台应用程序中的性能异常

我们推出了 Roots，这是一个全栈监控和分析系统，用于云平台即服务 (PaaS) 系统中的性能异常检测和瓶颈识别。Roots 有助于将应用程序性能监控作为 PaaS 云的核心功能，并使开发人员无需检测应用程序代码。Roots 跟踪对托管云应用程序的 HTTP/S 请求及其对 PaaS 服务的使用。为此，它采用了 PaaS 服务接口的轻量级监控。Roots 使用多种统计技术在后台处理这些数据，这些技术结合起来检测性能异常（即违反服务级别目标）。对于每个异常，Roots 都会确定该事件是由请求工作负载的变化还是由 PaaS 服务中的性能瓶颈引起的。通过关联跨 PaaS 不同层收集的数据，Roots 能够跟踪高级性能异常到云平台中特定组件的瓶颈。我们使用 AppScale PaaS 实现 Roots，并评估其开销和准确性。