Linked from
The 13 pages that link to Direct memory access, each with the reason it gives.
InterruptRelated: A device often interrupts the processor when a DMA transfer completes.
NVMeRelated: NVMe controllers use memory transfers to move data with limited processor involvement.
Expansion cardRelated: High-throughput cards can move data efficiently by using DMA.
Input/outputRelated: DMA reduces processor work during large I/O transfers.
FireWireRelated: FireWire can move data efficiently between peripherals and computer memory.