Credit-based flow control technique in a modular multiprocessor system

摘要

A credit-based, flow control technique utilizes a plurality of counters to conserve resources of a switch fabric within a modular multiprocessor system while ensuring that transaction packets pending in virtual channel queues of the fabric efficiently progress through those resources. The multiprocessor system includes a plurality of nodes interconnected by the switch fabric that extends from a global input port of a node through a hierarchical switch to a global output port of the same or another node. The resources include shared buffers within the global ports and hierarchical switch. Each counter is associated with a virtual channel queue and the flow control technique uses the counters to essentially create the structure of the shared buffers.