Jconsole and visual VM help monitor java applications in any environment. Here are a few additional details that can help you monitor your java applications better
Jconsole and permissions:
Jconsole lists the PIDs of local java applications when you start it. But what if there are java applications that are running under a different user ? Jconsole will not display those java PIDs that do not belong to the user who started Jconsole. The JConsole FAQ lists a few troubleshooting tips to get around this problem. You can alternatively expose the Jconsole connection through a remote port using the -Dcom.sun.management.jmxremote.port property. Securing the remote JMX URL with a username and password should do the trick.
Viewing Jconsole / JMC Beans with VisualVm:
Any system that logs vast amounts of information, needs to think about performance. The activity of logging cannot be a synchronous blocking call that returns only when the message has been logged to a persistence store. Enterprise logging systems usually make use of a message bus to carry messages asynchronously to their target persistence store. Be it a database or a file.
Talking about logging brings us to System.out.println() (Lets call is SOP for short). It is a surprisingly commonly method to “log” messages. SOP is not meant to be used as a logging system, but unfortunately there is no dearth of projects that have these statements scattered around the code base. The adverse effects that this statement can bring on the performance of the system is often not recognized as well as it should be.
Why is SOP a bottleneck for performance ? This is why…
