Recently, some new versions of java were made available. Most people think Java updates are boring and only security-oriented. But one of the last updates (7u40) includes a feature which deserves attention. I mean Java Mission Control 5.2.

Hotspot incoming

If you know the Oracle JRockit JVM a little bit, you might have heard about JMC, which was called JRockit Mission Control in the past. In fact, it’s a tool suite embedded with the Hotspot JDK since this so called 7u40 release which allows to monitor and profile your JVM.

Previously, it was only available for JRockit JVMs and it has now been ported to the Hotspot. JMC is a way more accurate and complete than JConsole or other embedded tools. It does not affect JVM performances more than 1%.

B006---JMCView1.png

Mission Completed

JMC gathers low level information thanks to its Flight Recorder tool which listens and waits for internal events. It can then monitor, manage, profile, and eliminate memory leaks from the JVM.

The new version of JMC now has a new browser with subnodes for available server side services with their states. It is supported by Eclipse 3.8.2/4.2.2 and later, it allows deeper management of MBeans, especially setting values directly in the attribute tree. It converges with JRockit event management: All information provided by JRockit is now available in the Hotspot as well.

B006---JMCView2.png

To enable JMC, you will have to add the following arguments to the JVM:

-XX:+UnlockCommercialFeatures
-XX:+|-FlightRecorder
-XX:+|-StartFlightRecording
-XX:FlightRecorderOptions=parameter=value

Sources

Oracle: http://www.oracle.com/technetwork/java/javase/2col/jmc-relnotes-2004763.html