EJB Remote threads once created are never released in JBoss EAP 6/7

Issue

• EJB threads once created are never released

[standalone@localhost:9999 /] /subsystem=ejb3/thread-pool=default:read-resource(include-runtime=true,include-defaults=true)

If we execute the above CLI command before calling the EJB , we see

{
    "outcome" => "success",
    "result" => {
        "active-count" => 0,
        "completed-task-count" => 0L,
        "current-thread-count" => 0,
        "keepalive-time" => {
            "time" => 100L,
            "unit" => "MILLISECONDS"
        },
        "largest-thread-count" => 0,
        "max-threads" => 10,
        "name" => "default",
        "queue-size" => 0,
        "rejected-count" => 0,
        "task-count" => 0L,
        "thread-factory" => undefined
    }
}

And now if we call the EJB several times we see that the "current-thread-count" => 10,"

This count never decreases

[standalone@localhost:9999 /] /subsystem=ejb3/thread-pool=default:read-resource(include-runtime=true,include-defaults=true)
{
    "outcome" => "success",
    "result" => {
        "active-count" => 0,
        "completed-task-count" => 98L,
        "current-thread-count" => 10,
        "keepalive-time" => {
            "time" => 100L,
            "unit" => "MILLISECONDS"
        },
        "largest-thread-count" => 10,
        "max-threads" => 10,
        "name" => "default",
        "queue-size" => 0,
        "rejected-count" => 0,
        "task-count" => 98L,
        "thread-factory" => undefined
    }
}

What is the reason for this ?