Java runtime metrics

APM Java Library version 3.1.0 and later

OTel semantic JVM metrics are collected via the runtime-telemetry instrumentation bundled by APM Java. The metrics are all prefixed with jvm.*.

Stable runtime metrics are automatically enabled by default. To disable, set false for one of the configuration options as described in the OpenTelemetry documentation:

• system property otel.instrumentation.runtime-telemetry.enabled

• environment variable OTEL_INSTRUMENTATION_RUNTIME_TELEMETRY_ENABLED

Additional configuration details can be found at the main runtime-telemetry README page, and in its shared library README.

There is also a jmx-metrics instrumentation that can be used to collect and report metrics provided by JMX through local MBeans available within the instrumented application. Collecting and reporting are provided out of the box for jetty, kafka-broker, wildfly, which are in addition to what the runtime-telemetry instrumentation provides; by default none are enabled. For JVM metrics the runtime-telemetry instrumentation is recommended. To enable collection of these metrics, set the following configuration options:

1. Enable JMX metric collections

   1. system property -Dotel.jmx.enabled=true

   2. environment variable OTEL_JMX_ENABLED=true

2. Enable collections for out of the box supported systems

   1. system property -Dotel.jmx.target.system=jetty,kafka-broker,wildfly

   2. environment variable OTEL_JMX_TARGET_SYSTEM=jetty,kafka-broker,wildfly

3. Enable collections for other systems based on configuration file

   1. system property -Dotel.jmx.config=path/to/config_file.yaml,more_rules.yaml

   2. environment variable OTEL_JMX_CONFIG=path/to/config_file.yaml,more_rules.yaml

The first configuration option must be set for the rest to take effect. Please see jmx-metrics for additional information.

APM Java Library versions earlier than 3.1.0

No pre-built dashboard is available for these legacy metrics.

The legacy runtime metrics are gathered from JMX MBeans and reported by the library on an interval. Reporting is enabled by default for the metrics described below. To disable reporting or enable additional JMX metrics, see Java JMX configuration.

• Legacy trace.jvm.* is still collected and configurable through config file. More information can be found here on how to configure.

Metric	Description
trace.jvm.GarbageCollector.*	JVM garbage collection cumulative values, plotted as derivatives in the JMX dashboard.
trace.jvm.Memory.*	Heap and non-heap memory details.
trace.jvm.MemoryPool.*	Memory pool details. A memory pool represents the memory resource managed by the JVM, for example Metaspace (PermGen).
trace.jvm.OperatingSystem.*	Operating system details, such as process CPU load.
trace.jvm.Runtime.*	Java process uptime.
trace.jvm.Threading.*	Thread details, such as thread count.