DMA Problems

Gabriel Dragffy dragffy at
Thu Apr 27 09:31:22 BST 2006

I type the "mount" command, and find my CD drive as so:
/dev/hdb on /media/cdrom0 type iso9660 (ro,noexec,nosuid,nodev,user=~)

I then check the DMA status as follows:
~@kokslick110:~$ hdparm /dev/hdb
 IO_support   =  0 (default 16-bit)
 unmaskirq    =  0 (off)
 using_dma    =  0 (off)
 keepsettings =  0 (off)
 readonly     =  0 (off)
 readahead    = 256 (on)
 HDIO_GETGEO failed: Invalid argument

It's off so I switch it on:
~@kokslick110:~$ sudo hdparm -d1 /dev/hdb
 setting using_dma to 1 (on)
 using_dma    =  1 (on)

OK, next I open up the hdparm conf to set it permanently:
kdesu kwrite /etc/hdparm.conf

And make sure it contains the following:
/dev/hdb {
	dma = on		   
#	write_cache = on

These are the steps as prescribed in the Wiki HowTo but dma doesn't seem to 
stay turned on after a reboot.  Can anyone see what the problem might be with 
what I have done?


More information about the kubuntu-users mailing list