Priority Queueing - Introduction Previous Next
This demo continues the story about the Littletown bank problem (how many tellers to provide) that was presented in the first simulation demo, Simulating a Basic Queueing System. If you haven't viewed that demo previously, you should do so now before continuing.
Recall that the first demo ended with management having made three decisions in planning for the opening of the bank.
  1. Build the bank with four teller windows. 
  2. Provide two tellers initially when the bank opens. 
  3. When the amount of business grows to exceed the level predicted for the long run (about one customer per minute), add a third teller.
As we pick up the story again, the bank now has recently opened and business is growing well. Currently, customers are arriving to receive teller service at the rate of about 50 per hour (so about one customer every 1.2 minutes on the average). Since this rate is less than the level above which a third teller would be added (about 60 per hour), the bank still is providing just two tellers.
Until very recently, the line lengths and waiting times for the customers have been quite reasonable. However, complaints about waiting are being made by one especially important kind of customer, local merchants. Since these busy merchants typically bring in very large deposits, it is vital that they be kept happy. Therefore, some change needs to be made to give them quicker service.