How to check JVM arguments from the CLI in WildFly

There are several options to collect JVM arguments of WildFly application server from the Command Line.

Firstly, if you want to check JVM arguments of a Java process, a simple way to do that is using the ‘jps‘ tool which is available in the ‘bin‘ folder of the JDK. Example:

jps -lvm
8239

-Djboss.server.base.dir=/home/jboss/wildfly-preview/standalone -D[Standalone] -Xms64m -Xmx512m -XX:MetaspaceSize=96M -XX:MaxMetaspaceSize=256m -Djava.net.preferIPv4Stack=true -Djboss.modules.system.pkgs=org.jboss.byteman -Djava.awt.headless=true --add-exports=java.base/sun.nio.ch=ALL-UNNAMED --add-exports=jdk.unsupported/sun.misc=ALL-UNNAMED --add-exports=jdk.unsupported/sun.reflect=ALL-UNNAMED -Dorg.jboss.boot.log.file=/home/francesco/jboss/wildfly-preview/standalone/log/server.log -Dlogging.configuration=file:/home/francesco/jboss/wildfly-preview/standalone/configuration/logging.properties

Also, you can use the jcmd command to get the same information:

jcmd pid VM.system_properties

Get JVM Arguments from the CLI

If you are running WildFly on a remote machine, then you can get the remote JVM settings of your server with the Command Line Interface (CLI) . In order to do that, you can query the platform-mbean node to get the JVM start up arguments:

[standalone@localhost:9990 /]  /core-service=platform-mbean/type=runtime:read-attribute(name=input-arguments)
{
    "outcome" => "success",
    "result" => [
        "-D[Standalone]",
        "-Xms64m",
        "-Xmx512m",
        "-XX:MetaspaceSize=96M",
        "-XX:MaxMetaspaceSize=256m",
        "-Djava.net.preferIPv4Stack=true",
        "-Djboss.modules.system.pkgs=org.jboss.byteman",
        "-Djava.awt.headless=true",
        "--add-exports=java.base/sun.nio.ch=ALL-UNNAMED",
        "--add-exports=jdk.unsupported/sun.misc=ALL-UNNAMED",
        "--add-exports=jdk.unsupported/sun.reflect=ALL-UNNAMED",
        "-Dorg.jboss.boot.log.file=/home/francesco/jboss/wildfly-preview/standal
one/log/server.log",
        "-Dlogging.configuration=file:/home/francesco/jboss/wildfly-preview/stan
dalone/configuration/logging.properties"
    ]
}

On the other hand, if you are running JBoss / WildFly in Domain mode, then you can collect the JVM settings as follows:

/host=primary/server=server-one/core-service=platform-mbean/type=runtime:read-attribute(name=input-arguments)

Make sure to replace the hostname and server name with your actual settings.

Get JVM Arguments from the Web Console

Finally, we will mention that it is also possible to get the JVM start up arguments from the Management Console by selecting the Runtime Tab and clicking on View in the Status Option.

From there, you will be able to see the JVM arguments of your WildFly Server:

Conclusion

In this article we have discussed how to get the JVM arguments in WildFLy either using the CLI and the Web management console.