1. A method comprising: at a network device, receiving a packet that includes a plurality of sets of header fields; parsing the packet to sequentially obtain the plurality of sets of header fields; predicting, based on a received first set of header fields made available at the network device, a predicted second set of header fields before a received second set of header fields is made available at the network device; and generating a network processing decision for the packet by: generating a first network processing decision result based on the received first set of header fields; generating a predicted second network processing decision based on the first network processing decision and the predicted second set of header fields; after the received second set of header fields is made available at the network device by the parsing, generating an actual second network processing decision based on the first network processing decision result and the received second set of header fields; and selecting for use as a second network processing decision result either the predicted second network processing decision or the actual second network processing decision.