DMA for smooth DVD playback

[Giles Burdett]

Hi everyone,

I recently discovered that my system didn't have DMA enabled, even though I
thought I had done everything necessary to enable it in the configuration of
the kernel etc. Then I found that I could use hdparm to truly enable DMA,
which of course resulted in much smoother DVD playback. But unless I missed
it, would it be possible to include a note about checking DMA settings with
hdparm in the INSTALL doc included in the archives? I think that may help
others new to playing DVDs under linux to achieve the best results from
their hardware.

On a related note, does anyone know a way to permanently enable DMA using
hdparm? I tried the -d1 -k1 option line, but despite the -k1 the -d1 didn't
stick between resets. I've resorted to putting the line "hdparm -d1
/dev/hdc" into my /etc/rc.d/rc.local to turn DMA on each time the system
boots. Is there a way of making this setting persist between resets/powerups
without this "work around"?

Thanks,

Giles

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| Giles Burdett                         |
| http://www.the-giant-sofa.demon.co.uk |
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