DMA
Definition
Direct Memory Access, device transfer to or from memory without CPU byte copying.
Detailed explanation
DMA means Direct Memory Access, which allows a device to transfer data to or from system memory without the CPU copying each byte. Drivers prepare buffers and descriptors, while an IOMMU can restrict which memory a device may address. DMA improves throughput but requires careful synchronization and security boundaries. Scatter/gather lists let a device operate on noncontiguous physical pages while presenting logical buffers to software. Cache coherency, transfer completion, address width, and cancellation all require coordination; otherwise fast autonomous access can expose stale data or memory outside the intended request.
Where you are likely to see it
This term usually appears in Device Manager, Windows recovery tools, Event Viewer, or the installation details for a device package. The definition above gives the short meaning; the detailed explanation describes the term's role in the operating system and hardware stack.
Device status, hardware IDs, and event text identify which Windows subsystem produced a label. This glossary is informational and does not provide repair, installation, or technical-support services.
Related vocabulary
Explore connected concepts and nearby entries in the Windows hardware vocabulary.
- WHQLWindows Hardware Quality Labs, Microsoft’s certification program for drivers.
- INF FileA Setup Information file that declares package installation and hardware support.
- DPC LatencyDelay associated with Windows Deferred Procedure Call processing.
- Filter DriverA driver that observes or modifies requests in another device stack.