1. A method comprising: periodically selecting a current parameter file from an active pool of a plurality of parameter files; periodically generating a plurality of testcases from the current parameter file and executing the plurality of testcases against a device, wherein the executing against the device hits events generated by the device over a plurality of periods; determining whether a number of the events hit by all of the testcases from the current parameter file in a current period meets a goal for the current parameter file for the current period; and if the determining is false, adding the current parameter file to a miss pool if a number of the events for all of the periods for the current parameter file does not meet a goal for all of the periods for the current parameter file.