1. A method comprising: monitoring network packet traffic events for a plurality of network interfaces in a packet processing device; comparing the monitored network packet traffic events to a first activity level to determine whether at least one of the network interfaces is near an overflow state; if the network interface is near an overflow state, then setting an overflow interrupt status bit in a status register of a queue manager for the corresponding network interface and generating an interrupt to request that packets of the corresponding network interface be processed; increasing a priority of the network interface in response to the overflow interrupt by changing a value in an interrupt mask register corresponding to the corresponding network interface for which the overflow interrupt status bit is set.