DMA is not enabling

usa1234 · 12-15-2008, 10:04 AM

Hi
I have SATA hard drive and under linux it is recongnized as /dev/sda. Following is the output of my /etc/hdparm.conf file;

Code:

/dev/sda {
        mult_sect_io = 16
        write_cache = on
        dma = on
}

When I issue command "sudo hdparm -d /dev/sda", it says;

Code:

star@alpha:~$ sudo hdparm -d /dev/sda

/dev/sda:
 HDIO_GET_DMA failed: Inappropriate ioctl for device

And the command "sudo hdparm -d1 /dev/sda" says;

Code:

star@alpha:~$ sudo hdparm -d1 /dev/sda

/dev/sda:
 setting using_dma to 1 (on)
 HDIO_SET_DMA failed: Inappropriate ioctl for device
 HDIO_GET_DMA failed: Inappropriate ioctl for device
star@alpha:~$

According to my knowledge, it shows that the DMA is not enabled, also when I do certain tasks like copying files, my system is under huge burden and I can do other tasks very difficultly. Can anyone help me that how can I solve this problem?
P.S I have following hardware;
Processor: Intel Dual Core 1.8 GHz
Motherboard: Asus P5N-MX (Core 2 quad support)
RAM: 1 GB
Hard Drive: 160 GB SATA (Western Digital)
Thanks

jschiwal · 12-15-2008, 11:18 AM

Is this for a pata drive or a sata drive. Sata drives are serial devices controlled by a sata controller so the dma options don't apply.

usa1234 · 12-15-2008, 12:22 PM

It is SATA drive. So what are the options for SATA drive?

jschiwal · 12-16-2008, 04:08 AM

AFAIK, dma may be integrated in the controller for the ram/controller side but the controller itself will determine the speed that it communicates with the drive. There is a sdparm program, but I think that deals with modifying scsi parameters which may not be applicable. The dma settings you are thinking of are analogous to the point settings in a carburetor. Modern cars use a different design, and don't have a carburetor with a rotor.

One thing you might want to check if you have a Western Digital drive is a jumper which reduces the speed of the drive from 3 GBs to 1.5 GBs. The sata controller in an external drive may operate at a slower rate, and probably has a WD drive with this jumper set. I think that new WD drives come with the jumper installed, so pulling it out will increase your speed if your controller can handle the faster speed.

usa1234 · 12-16-2008, 09:07 AM

Quote:

Originally Posted by jschiwal

One thing you might want to check if you have a Western Digital drive is a jumper which reduces the speed of the drive from 3 GBs to 1.5 GBs. The sata controller in an external drive may operate at a slower rate, and probably has a WD drive with this jumper set. I think that new WD drives come with the jumper installed, so pulling it out will increase your speed if your controller can handle the faster speed.

Thanks. I will definitely check the jumper and will post the results there

stratotak · 12-16-2008, 04:29 PM

Never heard of a carb with a rotor..lol.. I think you ment a distributor..not a carb..Cams connected to the distrubutor shaft,,rotor turns and makes contact with distributor cap..send juice to spark plug..then you have BANG..these days it controlled by the ECU..
http://en.wikipedia.org/wiki/Engine_Control_Unit