I wonder why they approached the problem from the way they did -- that is to say the monitor the effect of the problem but not the cause (# open fd caused by stuck threads). Why not monitor the # JVM threads.<p>I&#x27;m somewhat familiar with a tool we use at work for monitoring JVM - wily introscope, but I&#x27;m sure there are other options available (newrelic java agent? ps can check nwlp on Linux? prstat available on linux? other jmx solutions?). Again I&#x27;m not familiar with tomcat as much as websphere&#x2F;weblogic but I see tomcat has this option <a href="https:&#x2F;&#x2F;tomcat.apache.org&#x2F;tomcat-7.0-doc&#x2F;config&#x2F;valve.html#Stuck_Thread_Detection_Valve" rel="nofollow">https:&#x2F;&#x2F;tomcat.apache.org&#x2F;tomcat-7.0-doc&#x2F;config&#x2F;valve.html#S...</a> which you can use in conjunction with other monitoring to get alerts I think for situations like this (your app threads getting stuck). I&#x27;m not sure if tomcat will write a warning log msg or actually mark the the thread as &quot;STUCK&quot; in thread dump.<p>The author did mention Java Mission Control but I wanted to point out that&#x27;s not the only option for JVM monitoring.