hdparm question
 

I tried to check my hdparm setting on DVD, and indeed it is set to 0, so I would like to turn it on to improve my dvd performance during playback, instead, I get this message:

I issued this command while logged in as root----- hdparm -d 1 /dev/hdc

/dev/hdc:
setting using_dma to 1 (on)
HDIO_SET_DMA failed: Operation not permitted
using_dma = 0 (off)

Your drive might not be able to do that?

Are you sure that's your dvd drive, and also, I don't put spaces:
hdparm -d1 /dev/hdc

I don't know if that'll make a difference though.

Cool

/usr/sbin/hdparm -q -c3 -d1 -X udma4 -m16 /dev/hdX

That's the hdparm command I have setup in my rc.local script. You might need to tweak it a bit for that drive (like the udma) so that it will work, but that gave me a huge difference in my HARDdrive performance.

Cool

ok. will try again. I am sure that /dev/hdc is my dvd rom drive. I tried it without spaces and still the same.

Have you made sure DMA is "turned on" for this drive by your
BIOS? Does your kernel have support for DMA?

I am using redhat 8 with kernel 2.4.18-18.0 My dvd drive must be at least 8X or 16X

Post the output from:
dmesg | grep -i dma

It is something to do..
 

I had this problem last night, it is something to do with Redhat messing up dma support as far as I know..

I do have a line that you can do that fixes it, I can't remember it right now.. but I do have the line noted at home. If you still haven't gotten the problem fixed I will post it later today..

thanks

I'm having the same problem- I get that error: HDIO_SET_DMA failed: Operation not permitted. I want to set the dma for my hard drive, but it never lets me. I have a Maxtor 40 gig 7200 RPM which is fairly new and fast. I tried setting something in the bios called dma but it still won't work. Any other ideas?

Apologies
 

Hey,
Sorry for the delay.. if you still need it..

Make sure you are logged in as root, open up a terminal and type

echo options ide-cd dma=1 >> /etc/modules.conf

DMA should now be enabled

Yes. I still need it. I will try your suggestion. Just to confirm, do I type the line 'echo options ide-cd dma=1' inside /etc/modules.conf ???


Thanks again.

No.. you..
 

You, you type that entire line on the command prompt. I don't fully understand what it does, but I think it inserts that line into the modules.conf, thats why I say type that entire line rather than copy anything into modules.conf.

Just open up the terminal as root and type that line.

Still won't work

the same output is returned

Are you...
 

Are you still trying to run the hdparm command? You don't have too. Once you have entered that line, restart the machine and it is done. My DVD playback worked fine after I did it.