Guaranteed bandwidth allocation method in a computer system for input/output data transfers

The present invention discloses a novel arbitration procedure for selecting among devices in a computer system requesting access to a single resource such as, for example, a system bus or main memory. The arbitration procedure provides an efficient means for guaranteeing the available system bus bandwidth to devices having high bandwidth requirements. Each device can be allotted a certain amount of bandwidth that is guaranteed to be available for that device within a given time interval. Excess bandwidth not consumed by the guaranteed allotments can be used as remainder (e.g., available but not guaranteed) bandwidth by the devices. The arbitration procedure further provides a guaranteed maximum latency so that no device is prevented from completing data transfers in a timely manner. The arbitration procedure still further provides the ability to dynamically program the amount of the bandwidth that is guaranteed a particular device. The arbitration procedure can be applied to a number of different communication platforms and bus protocols.