What is gmx ? gmx is an experimental package for instrumenting Go applications. gmx is similar to Java’s jmx and provides a simple method of querying the internal state of your Go application by invoking anonymous functions bound to published keys. Here is an example using the included client, gmxc. % ./gmxc -p 16378 runtime.version runtime.numcpu os.args os.args: [./godoc -v -http=:8080] runtime.