A target device in a computer bus system allocates resources by selecting a priority
requester for allocation of scarce resources. In a non-bus arbiter configuration,
the first initiator device to receive a retry response to a transaction request
after the resources are exhausted is designated as a priority requester. In a bus
arbiter configuration, the priority requester is chosen on a round-robin basis
from initiator devices that received a retry response to the initiator's most recent
transaction request. If only one resource is available when an initiator sends
a transaction request, the initiator receives a retry response unless the initiator
is the priority requester.
