An online education platform deploys applications to the Huawei Cloud ServiceStage platform for full lifecycle management of the applications. During use, a relatively large latency was discovered…

An online education platform deploys applications to the Huawei Cloud ServiceStage platform for full lifecycle management of the applications. During use, a relatively large latency was discovered. The operations engineer used a distributed call chain analysis tool for analysis. Which of the following resources is the core of this method for monitoring?