For one of our project we are facing jrun high usage issue. When looking into task manager (Window 2008) I found jRun continously eating up 50% CPU usage even though there is no traffic (or may be 2 to 3 users) only on site. Initially I tried to install FusionReactor to get all kind of detail regarding ColdFusion. Started with trial version and thought if useful then get full version but it seems that giving me all application ColdFusion application related information but can't find anything why JRun eating 50% of CPU usage. After bit googing I found VISUALVM and JConsole for monitoring and troubleshooting java application. I like VisualVm due to it's nice GUI and also I can integrate JConsole as plugin to it. It win - win kind of situation.