APM Agents periodically collect performance metric data to measure the overall health status of applications. They can collect the metric data of JVM, GC, service calls, exceptions, external calls, database access, and middleware, helping you comprehensively monitor application running.
APM has strict definitions on metric data collection. Each type of data to be collected corresponds to a collector. For example, for JVM data of Java applications, a JVM collector is provided. A collector collects data of multiple metric sets. For details about collectors and metric sets, see Collection Center.
After collectors are deployed in the environment, monitoring items are generated. During data collection, the monitoring items determine data structures and collection behaviors.
Agents automatically discover collection plug-ins and instantiate collectors to form monitoring items. Monitoring items are instantiated in an environment.
There are many types of collectors, which are hard to distinguish. The system backend groups collectors for easy data query.
Based on collector functions, monitoring items can be classified into:
Collectors corresponding to monitoring items define collection parameters. You can modify collection parameters on the page as required. These parameters will be delivered to Agents with heartbeat parameters to change collection behaviors. By default, Redis instruction content is not collected for security purposes. If necessary, modify collection parameters to collect specific instruction data. Collection parameters can also be defined on environment tags. Collectors automatically inherit collection parameter attributes of corresponding environment tags. In this way, configuration is automated.
On the metric monitoring details page, a monitoring item corresponds to one or more tab views, and each view corresponds to a metric set. APM provides summary tables, trend graphs, latest data tables, and original tables. For details, see Monitoring Item Views.