how to determine whether a queue is empty in Simevents and do some actions based on this observation?
<p>I want to model a queue with vacations. When the queue is empty, the server will have a period of vacation with certain distribution.(I can use use gate to block the server ) So I need to get the data of the number of entity in queue block. Could you please tell me how to do that?</p>

<p>Many thanks.</p>