= Keycloak uses Micrometer for metrics

Keycloak provides an optional a metrics endpoint which exports metrics in the Prometheus format.
In this release the implementation to provide this data switched from SmallRye to Micrometer, which is the https://quarkus.io/guides/micrometer[recommended metrics library for Quarkus].

Due to this change, metrics have been renamed.
The following table shows some examples.

Before upgrading it is recommended to review all metrics returned from the endpoint before and after the change, and update their usage in dashboards and alerts.

.Examples of changed metrics names
|===
|Old metric name |New metric name

|`base_gc_total`
|`jvm_gc_pause_seconds_count`

|`base_gc_time_total_seconds`
|`jvm_gc_pause_seconds_sum`

|`base_thread_count`
|`jvm_threads_live_threads`

|`vendor_agroal_*`
|`agroal_*`

|===
