1. A method for scheduling a crossbar using distributed request-grant-accept arbitration between input group arbiters and output group arbiters in a switch unit, the method comprising: receiving, at a group arbiter communicably coupled to a group comprising a plurality of links of the switch unit, an indication that the group has won an arbitration slot, wherein multiple links of the group are candidates able to satisfy the arbitration slot; determining a first link identifier having a highest priority within an ordered queue among link identifiers in the ordered queue matching the candidates able to satisfy the arbitration slot; selecting a first link of the group corresponding to the first link identifier to satisfy the arbitration slot; and updating, by operation of one or more computer processors, the ordered queue based on the selected first link, wherein the first link identifier is moved to a bottom of the ordered queue.