The Java SE Platform includes Java Management Extensions (JMX). JMX is a way to monitor and manage applications, devices, and services. Generally, application servers have built-in JMX metrics that you can monitor.
New Relic's Java agent offers the ability to monitor specific metrics from MBeans and attributes in your application without modifying code by using a custom instrumentation YAML file. The Java agent will read the YAML file on startup and record the specific metrics. To view custom JMX metrics, use the New Relic Insights Metric Explorer.
Access to this feature depends on your subscription level.
The Java agent only sees metrics from MBeans in your current JVM. If the MBeans are being accessed remotely, or exist in a separate JVM, they will not be available to the New Relic Java agent.
To learn more about importing JMX data into New Relic, watch this video (approximately seven minutes).
File structure rules
The custom instrumentation file must be in the YAML format. Use a YAML validator to ensure the syntax is accurate before using the file with New Relic's Java agent, and follow these rules:
- YAML files are case sensitive.
- All indentations are in increments of two characters. Data in the same stanza of the file must use the same level of indentation. Indent any sub-stanzas by an additional two spaces.
- You must restart your JVM host process for changes to take effect.
Here is a summary of each property in the JMX file. For more information, see Custom JMX YAML examples.
||The primary descriptive name identifying your YAML custom instrumentation file. Include one space before the
||The version of the extension file. If two extensions have the same name, only the extension with the highest version will be used. Be sure the version property is on a separate line from
||No value follows the property
||Matches the specific MBean's object. If you are using JDK version 1.6 or higher, the
||Available with New Relic's Java agent version 3.7.0 or higher. An optional property that provides the ability to name the metric used in New Relic. To use
||There is no value on the metrics line. Include four spaces before metrics.|
||A comma-separated list of the MBean's attributes. The attribute name must match exactly. Include 6 spaces before the dash and one space between the dash and
YAML file location
The Java agent reads the YAML file on process startup. There are two ways to specify the YAML file location:
- Create an extensions directory
- In the directory where the
newrelic.ymlare located, create a directory named
- Put the YAML file in this directory with a
newrelic.yml, check that the property
extensions.diris not set.
- In the directory where the
- Specify an existing extensions directory
- In the
newrelic.ymlconfiguration file under the common section, use the property
extensions.dirto specify the directory where the YAML file is located.
- Make sure the file is in the specified directory and that the file has a
- In the
The custom metric will not work if there is more than one YAML file in the same folder as the agent. Move backups and copies to another folder when customizing.
Verify the file was read
To verify the YAML file was read by the agent:
- Open the
- Change the log level property to
- Start up the application.
Verify that the
logs/newrelic_agent.logfile includes a statement indicating that the file was read in:
Reading custom extension file /path/to/file/file.yml
- If you cannot find this statement, check the location of the YAML file. Also make sure the process has read access to the file.
Verify that the file includes this statement:
Adding extension with name NAME_FROM_YAML and version VERSION_FROM_YAML
- If you cannot find this statement, verify that the document was parsed correctly. Also verify if there is another extension file with the same name and a higher version number.
View custom JMX metrics in Insights
In order to view custom JMX metrics, use the New Relic Insights Metric Explorer to search and create customized charts. To view your JMX counters in Insights:
- From insights.newrelic.com > Data explorer > Metrics, select the application that contains JMX counters.
- Search for JMX or for the direct path to the counter as set in your YAML file.
- Search for the direct path to your counters
- Example YAML file
name: TomcatCustom version: 1.0 enabled: true jmx: - object_name: java.nio:type=BufferPool,name=* metrics: - attributes: Count type: monotonically_increasing
You can find counters from the object in the example YAML file by searching in the Metric Explorer for the following:
For more information about how metrics are named and stored, see Custom JMX YAML examples.