An Acronym for Direct Memory Access

A method for peripherals (eg PCI and IDE devices) to copy data directly into a memory buffer, rather than explicitly being copied by the CPU. -- AddToMe -- Is this factually correct? -- JohnMcPherson.

For example, sound cards used to use DMA, although the drivers generally don't bother any more. (The famous sb16 did, at least).

It can significantly speed up data transfers for HardDisks and CDROMs.

UDMA (Ultra DMA) specifies a couple of faster transfer rates over standard DMA.

See also:

• /proc/dma [shows you "DMA channels" (used by PCI cards?)?

hdparm(8), HowToUltraDMA?