Metrics Endpoint

Spring Boot provides a metrics endpoint that you can use diagnostically to examine the metrics collected by an application. The endpoint is not available by default and must be exposed. See exposing endpoints for more details.

Navigating to /actuator/metrics displays a list of available meter names. You can drill down to view information about a particular meter by providing its name as a selector — for example, /actuator/metrics/jvm.memory.max.

The name you use here should match the name used in the code, not the name after it has been naming-convention normalized for a monitoring system to which it is shipped. In other words, if jvm.memory.max appears as jvm_memory_max in Prometheus because of its snake case naming convention, you should still use jvm.memory.max as the selector when inspecting the meter in the metrics endpoint.

You can also add any number of tag=KEY:VALUE query parameters to the end of the URL to dimensionally drill down on a meter — for example, /actuator/metrics/jvm.memory.max?tag=area:nonheap.

The reported measurements are the sum of the statistics of all meters that match the meter name and any tags that have been applied. In the preceding example, the returned Value statistic is the sum of the maximum memory footprints of the “Code Cache”, “Compressed Class Space”, and “Metaspace” areas of the heap. If you wanted to see only the maximum size for the “Metaspace”, you could add an additional tag=id:Metaspace — that is, /actuator/metrics/jvm.memory.max?tag=area:nonheap&tag=id:Metaspace.