Credit based flow control scheme over virtual interface architecture for system area networks

摘要

A transport service provider provides a credit-based flow control scheme and is designed to operate over VI Architecture. The credit-based flow control scheme reduces overhead (e.g., reduces buffer copies and kernel processing) by relying upon the reliability properties of the underlying VI Architecture. If the number of send credits is sufficient, then the sender prepares and sends the packet. Otherwise, the sender sends a Credit Request and waits for a Credit Response. Upon receiving the corresponding Credit Response, the sender continues sending data packets. In response to a sender's Credit Request, the receiver sends the Credit Response only when it has enough receive credits (above a threshold value or low water mark).