A broad explanation about processor sharing system, both in egalitarian (PS) and discriminatory processor system (DPS) and its implication to the auction. It explains the potential of improving the revenue of the system. At first, the customer's willingness-to-pay (WTP) and rational behavior will be defined. The WTP of customer is defined as the function of the throughput of the system. Based on the WTP function, two types of customer rational behaviors are defined and applied to the PS model and the DPS model. Good literature overview with a balance of technical contents and numerical work.