Policy function schedulers provide a flexible framework for implementing a wide range of different scheduling schemes. In such schedulers, the priority of a job at any instant in time is defined by the difference between the time it spent in the system and an arbitrary function of its attained service time. The latter is called the policy function and acts as the functional parameter that specifies a particular scheduling scheme. For instance, a constant policy function specifies the first-come, first-serve scheduling scheme. By changing the policy function, the system behavior can be adjusted to better conform with desired response characteristics. It is common to express response characteristics in terms of a response function, the average response time of a job conditioned on its service requirement in equilibrium.   In this paper, we analyze processor-sharing M/G/1 systems in which the priorities of different classes of jobs are determined by distinct policy functions.
['Manfred Ruschitzka']
The response of job classes with distinct policy functions(Extended Abstract)