Message transfer system and method for parallel computer with message transfers being scheduled by skew and roll functions to avoid bottlenecks

摘要

A computer system comprises a plurality of processing elements interconnected by a communications network. The communications network has a series of network addresses each identifying a location in the network, each processing element has an associated network address in the series. The communications network transfers messages transmitted by the processing elements in accordance with a respective address portion associated with each message, thereby to transfer the messages among the processing elements. Each processing element includes a message generator and a message transmitter. The message generator generates, during a message transfer operation, a series of messages for transmission over the communications network to others of the processing elements in the system, each message having an address portion whose contents enable the communications network to transfer the message from the processing element generating the message to a processing element to receive the message. The message generator generates the messages such that address portions of the successive messages in the series are transferred to processing elements having successive network addresses. The message transmitter iteratively transmits the series of messages generated by the message generator, the message transmitters of the processing elements which have successive network addresses selecting, as initial messages to be transmitted, messages having address portions to be transmitted to processing elements which have succeeding network addresses, thereby to effect a skewing of the messages transferred over the communications network.