||This interface represents a response time controller, invoked by the
stage's thread manager to manipulate admission control policies to
meet a response time target.
||This interface allows various components of the system to record and
gather statistics about the stage during execution.
||A StageWrapperIF is the internal representation for an application
stage - an event handler coupled with a set of queues.
||SystemManagerIF is an internal interface allowing modules
to access systemwide features.
||A ThreadManagerIF is responsible for creating, managing, and scheduling
threads across a set of stages.