DMA

[John McCabe-Dansted]

On 5/24/06, Scott James Remnant <scott at ubuntu.com> wrote:
> If DMA is not enabled by default on your machine (how did you find out
> whether it was or wasn't, btw?)

The normal way to find out that DMA is not enabled is to try playing a
DVD and finding that "it is jerky". The other way is to try burning a
DVD and discover that you keep getting buffer underruns.

On the machines I've used DMA had to be manually set in userspace, and
you could not do anything in realtime without it,  (e.g on a 1.6 GHZ
machine). Since DMA was never automatically enabled by the kernel on
any of the machines I've owned (that I recall), I have assumed that
this was what everybody did.

-- 
John C. McCabe-Dansted
PhD Student
University of Western Australia