Direct Memory Access or DMA is a simple concept to grasp. As the name implies, something is accessing host memory directly—presumably bypassing something else. In the case of an Accolade SmartNIC, the adapter itself is the one directly accessing host memory and bypassing the host CPU in the process. In other words, with DMA the host CPU is not burdened with having to deal with copying data from the SmartNIC into host memory for consumption by the host application.
Since the CPU is not burdened with this processor intensive task, it is free to perform higher value functions which is ultimately the purpose of using a SmartNIC in the first place. So simply put, after all packet processing concludes, a SmartNIC efficiently transfers all relevant packets and associated packet descriptors (metadata) across the PCIe bus directly in to host memory for consumption by the host application
To test drive an Accolade SmartNIC please contact us at email@example.com