4.2. General Diagnostics

  1. Verify the back end server is responsive by making a direct request to it.
  2. Monitor high load using one of the following methods:
    Twiddle
    1. Locate the appropriate Twiddle script for your environment (twiddle.sh, twiddle.bat or twiddle.jar) in the <JBOSS_HOME>/bin/ directory.
    2. Run the following command: 
      <TWIDDLE> -u admin -p password get "jboss.web:name=ajp-127.0.0.1-8009,type=ThreadPool"
      Use the script appropriate to your operating system and environment .
      Twiddle may need to be modified for each specific environment, but the above will work in a default JBoss instance where no ports have been changed and JBoss is starting on the localhost.
    JMX Console
    1. Navigate to http://localhost:8080/jmx-console.
    2. Find the jboss.web section.
    3. Click on name=ajp-localhost/127.0.0.1-8009,type=ThreadPool (or whichever AJP ThreadPool matches your environment)
    4. Investigate the currentThreadsBusy attribute. If this attribute is reaching the maxThreads there will be a problem as JBoss Web is reaching the defined ThreadPool capacity.