Hi
1) I think that you need to install either the OpenJVM or the Sun/Oracle JVM, and then set JAVA_HOME to that JVM.
2) and 3) question
Example that you can use with twiddle
To get the active session count for your own app.
./twiddle.sh --user=admin --password=admin --server=127.0.0.1 get jboss.web:type=Manager,path=/jmx-console,host=localhost activeSessions
To retrieve the thread queue size
./twiddle.sh --user=admin --password=admin --server=127.0.0.1 get jboss.system:service=ThreadPool QueueSize
To retrieve active thread counts
./twiddle.sh --user=admin --password=admin --server=127.0.0.1 get jboss.system:type=ServerInfo ActiveThreadCount
To retrieve the amount of free memory
./twiddle.sh --user=admin --password=admin --server=127.0.0.1 get jboss.system:type=ServerInfo FreeMemory
To get all processing stats from the HTTP acceptor on JBoss
./twiddle.sh --user=admin --password=admin --server=127.0.0.1 get jboss.web:type=GlobalRequestProcessor,name=http-127.0.0.1-8080
Invoke a thread dump
./twiddle.sh --user=admin --password=admin --server=127.0.0.1 invoke jboss.system:type=ServerInfo listThreadDump
Invoke a listing of CPU utilization
./twiddle.sh --user=admin --password=admin --server=127.0.0.1 invoke jboss.system:type=ServerInfo listThreadCpuUtilization
Total System memory
./twiddle.sh --user=admin --password=admin --server=127.0.0.1 get jboss.system:type=ServerInfo TotalMemory
Active Thread Count
./twiddle.sh --user=admin --password=admin --server=127.0.0.1 get jboss.system:type=ServerInfo ActiveThreadCount
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