A network appliance can have an input port that can receive network packets at line rate, two or more ingress queues, a line rate classification circuit that can place the network packets on the ingress queues at the line rate, a packet buffer that can store the network packets, and a sub line rate packet processing circuit that can process the network packets that are stored in the packet buffer. The line rate classification circuit can place a network packet on one of the ingress queues based on the network packet's packet contents. A buffer scheduler can select network packets for processing by a sub line rate packet processing circuit based on the priority levels of the ingress queues.