ejb3/src/main/java/org/jboss/as/ejb3/timerservice/TimerServiceImpl.java
public boolean shouldRun(TimerImpl timer) {
        // check peristent without further check to prevent from Exception (WFLY-6152)
        return !timer.isTimerPersistent() || timerPersistence.getValue().shouldRun(timer, ContextTransactionManager.getInstance());
    }
public boolean shouldRun(TimerImpl timer) {
        // check peristent without further check to prevent from Exception (WFLY-6152)
        return !timer.isTimerPersistent() || timerPersistence.getValue().shouldRun(timer, ContextTransactionManager.getInstance());
    }
Check if a persistent timer is already executed from a different instance
or should be executed.
For non-persistent timer it always return <code>true</code>.

@param timer the timer which should be checked
@return <code>true</code> if the timer is not persistent or the persistent timer should start