A service policy is a named set of overrides to the performance goals and processing capacity boundaries in the service definition. A policy applies to all of the work running in a sysplex. Because processing requirements change at different times, service level requirements may change at different times. If you have performance goals that apply to different times or a business need to limit access to processor capacity at certain times, you can define multiple policies.
In order to start workload management processing, you must define at least one service policy. You can activate only one policy at a time.