[SWLUG] ide=nodma question

[Foeh Mannay]

Hi,

asura at theexcession.co.uk wrote:
> with an amd x2 
> 3800 how much slower will this make my disk access, are there only 
> certain types of apps where i would notice a slowdown?

Well, for whatever worth it is for a comparison, I once compiled a 
kernel without support for my hard disk controller so it couldn't use 
DMA any more. It took *ages* to boot, and a long time to open apps. Also 
took a while to compile the kernel again to fix it! That was on an 
AMD-K6-2 450 (circa 2000), which was a renownedly rubbish setup and 
probably worsened the problem considerably.

If the slowdown is as bad on your system as it was on mine, it will be 
quite unbearable.

Isn't there a hdparm flag you can use to disable DMA? I'm sure in the 
olden days I used to use hdparm to enable DMA so you'd think the reverse 
would be possible. Should give you a feel for the speed of it without 
DMA, at least at an application level before you make your mind up what 
to do.

Foeh