A high-speed credit-based allocator circuit receives an allocation request to make an allocation to one of a set of a processing entities. The allocator circuit maintains a chain of bubble sorting module circuits for the set, where each bubble sorting module circuit stores a resource value and an indication of a corresponding processing entity. A bubble sorting operation is performed so that the head of the chain tends to indicate the processing entity of the set that has the highest amount of the resource (credit) available. The allocation requested is made to the processing entity indicated by the head module circuit of the chain. The amount of the resource available to each processing entity is tracked by adjusting the resource values as allocations are made, and as allocated tasks are completed. The allocator circuit is configurable to maintain multiple chains, thereby supporting credit-based allocations to multiple sets of processing entities.