Hello fellow Slackers,

I have an LG DVD writer which is capable of writing at 16x, and have been having a small problem with it under Linux over the past few months.

Currently, I am running Linux-2.6.16.11 with Slackware 10.2.

What happens is that DMA occasionally disables itself on the drive. I don't usually notice until I've started writing a DVD and it won't go faster than 1.9x.

Re-enabling DMA with a quick fixes it every time, but I'm just wondering why DMA would disable itself?

This started happening back when I upgraded from 2.6.11 to 2.6.14, and has happened intermittently ever since. Most of the time, I can fire up Slackware and burn a disc at full speed without having to tell hdparm anything.

It is no biggie, since I can add the above command to /etc/rc.d/rc.local, but I'd just like to know why it happens?

Also, would it help to run an 80 wire IDE cable in place of the 40 wire cable which is currently installed?

Cheers/Ciao,


Rob.

man hdparm. There is a switch to store that for you. You must store it or it goes back to defaut(off).

That being the case, it should be off all the time no? So far this year it has only switched itself off a couple of times.

Anyhow, I'll tell hdparm to store the setting, and watch it over the next few months.

I put the command in /etc/rc.d/rc.local and have never had a problem with it turning itself off. Original (2.4) kernel.