OUTPUT QUEUEING WITH SCALABILITY FOR SEGMENTED TRAFFIC IN A HIGH-RADIX SWITCH

Examples describe an egress subsystem that can be used to schedule fetching and transmission of packets from a switch fabric. Segments of a packet can be requested from a switch fabric and stored in a re-order buffer to re-order any segments that are received out of order from the switch fabric. A header segment re-order buffer can be used to re-order segments of a header. After a header of a packet is available in the header segment re-order buffer, the header can be processed before the entire associated body is received from the switch fabric. A jitter threshold scheme can gate egress of a body from a re-order buffer unless a time threshold or amount threshold is met. The egress subsystem can track a state of packet segments from request to transmission, A flow control message received at the egress subsystem can cause packets in certain states to be paused and not permitted to egress.