HikariCP JMX – Unable to split Pool metrics by pool name when multiple pools exist in the same JVM

Mouadrhm — Tue, 05 May 2026 09:38:56 GMT

Hi everyone,

I’m working with Dynatrace Managed on prem and a custom JMX extension to collect HikariCP metrics.

I can successfully collect metrics from both:

com.zaxxer.hikari:type=PoolConfig
com.zaxxer.hikari:type=Pool

There is however an important difference between the two:

PoolConfig exposes a PoolName attribute → I can define a dimension (e.g. pool.name) and split metrics per pool
Pool does not expose the pool name as an attribute → the pool name only appears in the ObjectName display, not as a key property

Because of this, when multiple Hikari pools run in the same JVM, Dynatrace:

collects Pool metrics correctly
but aggregates them at JVM level
making it impossible to split runtime metrics (ActiveConnections, IdleConnections, etc.) per pool

Example:

Pool A: IdleConnections = 2
Pool B: IdleConnections = 5
Dynatrace reports: IdleConnections = 7 for the same process

This makes per‑pool monitoring and alerting unreliable.

Constraints:

I cannot modify the application code
I cannot change how HikariCP exposes its JMX MBeans
Only the Dynatrace side (extension/configuration) can be adjusted

Question:
Is this a known limitation with HikariCP JMX in Dynatrace Managed?
Is there any supported Dynatrace‑side workaround to avoid Pool metric aggregation when multiple pools exist in the same JVM?

Thanks in advance for any feedback or guidance.
My extension code :

name: custom:hikari.jmx.metrics version: 1.0.1 minDynatraceVersion: 1.303.0 author: name: M metrics: - key: hikari.connections.active metadata: displayName: Hikari Active Connections unit: Count - key: hikari.connections.idle metadata: displayName: Hikari Idle Connections unit: Count - key: hikari.connections.total metadata: displayName: Hikari Total Connections unit: Count - key: hikari.threads.awaiting metadata: displayName: Hikari Threads Awaiting Connection unit: Count - key: hikari.connections.acquired metadata: displayName: Hikari Connections Acquired unit: Count - key: hikari.connections.created metadata: displayName: Hikari Connections Created unit: Count - key: hikari.connections.timeout metadata: displayName: Hikari Connections Timeout unit: Count - key: hikari.config.connection.timeout metadata: displayName: Hikari Connection Timeout unit: MilliSecond - key: hikari.config.idle.timeout metadata: displayName: Hikari Idle Timeout unit: MilliSecond - key: hikari.config.max.lifetime metadata: displayName: Hikari Max Lifetime unit: MilliSecond - key: hikari.config.validation.timeout metadata: displayName: Hikari Validation Timeout unit: MilliSecond - key: hikari.config.minimum.idle metadata: displayName: Hikari Minimum Idle unit: Count - key: hikari.config.maximum.pool.size metadata: displayName: Hikari Maximum Pool Size unit: Count - key: hikari.config.leak.detection.threshold metadata: displayName: Hikari Leak Detection Threshold unit: MilliSecond - key: hikari.config.keepalive.time metadata: displayName: Hikari Keepalive Time unit: MilliSecond - key: hikari.config.initialization.fail.timeout metadata: displayName: Hikari Initialization Fail Timeout unit: MilliSecond jmx: groups: - group: hikari subgroups: # ========================= # POOL (pool.name depuis ObjectName) # ========================= - subgroup: pool query: "com.zaxxer.hikari:type=Pool (*)" dimensions: - key: pool.name value: property:name metrics: - key: hikari.connections.active type: gauge value: attribute: ActiveConnections - key: hikari.connections.idle type: gauge value: attribute: IdleConnections - key: hikari.connections.total type: gauge value: attribute: TotalConnections - key: hikari.threads.awaiting type: gauge value: attribute: ThreadsAwaitingConnection - key: hikari.connections.acquired type: count value: attribute: ConnectionsAcquired - key: hikari.connections.created type: count value: attribute: ConnectionsCreated - key: hikari.connections.timeout type: count value: attribute: ConnectionsTimeout # ========================= # POOL CONFIG (pool.name via attribute) # ========================= - subgroup: poolconfig query: "com.zaxxer.hikari:type=PoolConfig (*)" dimensions: - key: pool.name value: attribute: PoolName metrics: - key: hikari.config.connection.timeout type: gauge value: attribute: ConnectionTimeout - key: hikari.config.idle.timeout type: gauge value: attribute: IdleTimeout - key: hikari.config.max.lifetime type: gauge value: attribute: MaxLifetime - key: hikari.config.validation.timeout type: gauge value: attribute: ValidationTimeout - key: hikari.config.minimum.idle type: gauge value: attribute: MinimumIdle - key: hikari.config.maximum.pool.size type: gauge value: attribute: MaximumPoolSize - key: hikari.config.leak.detection.threshold type: gauge value: attribute: LeakDetectionThreshold - key: hikari.config.keepalive.time type: gauge value: attribute: KeepaliveTime - key: hikari.config.initialization.fail.timeout type: gauge value: attribute: InitializationFailTimeout

topic HikariCP JMX – Unable to split Pool metrics by pool name when multiple pools exist in the same JVM in Extensions

HikariCP JMX – Unable to split Pool metrics by pool name when multiple pools exist in the same JVM