Patent ID: 8037213

Claim:
A method of replenishing data descriptors in a Direct Memory Access (‘DMA’) injection first-in-first-out (‘FIFO’) buffer, the method comprising: determining, by a messaging module on an origin compute node, whether a number of data descriptors in a DMA injection FIFO buffer exceeds a predetermined threshold, each data descriptor specifying an application message for transmission to a target compute node; queuing, by the messaging module, a plurality of new data descriptors in a pending descriptor queue if the number of the data descriptors in the DMA injection FIFO buffer exceeds the predetermined threshold; establishing, by the messaging module, interrupt criteria that specify when to replenish the injection FIFO buffer with the plurality of new data descriptors in the pending descriptor queue, wherein establish interrupt criteria includes injecting a replenish descriptor in the injection FIFO buffer, the replenish descriptor specifying a DMA data transfer operation to notify the messaging module when to replenish the injection FIFO buffer with the plurality of new data descriptors in the pending descriptor queue; and injecting, by the messaging module, the plurality of new data descriptors into the injection FIFO buffer in dependence upon the interrupt criteria.