Abstract: Methods and apparatus are disclosed for scheduling entities in a system, such as, but not limited to a computer or communications system. Typically, calendar scheduling is used as a primary scheduling mechanism, with spare time allocated to a secondary scheduling mechanism. The secondary scheduling mechanism can use a round robin technique or variant thereof, or any other scheduling methodology. A calendar entry is examined to determine whether to process a calendar scheduled entity corresponding to the calendar entry or to process a secondary scheduled entity. Which scheduling entity to process is typically determined based on an eligibility of an entity corresponding to the primary scheduled event, a scheduling mechanism indicator, and/or an entity indicator. These combinations of scheduling mechanisms can be used to identify which packets to send, queues or ports to access, processes or threads to execute, or for any other purpose.