Lets start

[Miles]

DMA is automatically configured by the operating system for most
devices. A significant device where DMA may not be automatically
configured is on the system parallel ata (PATA) disks. For PATA devices
(see section below) DMA access can be enabled, assuming your device
is /dev/hda (SATA drives which are popular today do not use DMA in the
conventional sense) by running the command:
hdparm -d1 /dev/sda
To see the current setting on your hard disk you can run the command
hdparm -d /dev/sda
Configuring IRQ

my output from the above commands are

miles@P4:~$ 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

sudo hdparm -d /dev/sda

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

Whats missing that ioctl (input/output controller methinks) is
inappropriate? Is it something I gotta find and change in BIOS?
Thanks
Miles

[Raoul Snyman]

Firstly, do you actually have a device called /dev/sda ?

Additionally, this is what you are missing:

> (SATA drives which are popular today do not use DMA in the
> conventional sense)

--
Raoul Snyman
B.Tech Information Technology (Software Engineering)
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[Miles]

yip Raoul

Here are some pastebin links with the relevant commands taken from some
of the commands I found in the bug goodies at launchpad
http://slexy.org/view/s2zcyOxfB7
http://slexy.org/view/s2MqdVIcTc
http://slexy.org/view/s20cGx2897

[Neil Oosthuizen]

Note that this is for IDE and EIDE devices (PATA and not SATA) and that you should have a device /dev/hdx to indicate this before the command could be useful. If you have devises labeled /dev/sdx it means you have SATA (or SCSI or USB but I digress) and SATA already has DMA of sorts enabled...  Well that is what I get from this section anyway :p


Neil

[Miles]

-----Original Message-----
From: Neil Oosthuizen <nls...@gmail.com>
Reply-to: linux-...@googlegroups.com
To: linux-...@googlegroups.com
Subject: Re: [lpi] Lets start

Neil

--
[Linux Studies Group -
http://groups.google.com/group/linux-studies/about]

Thanks Neil, I have an ide drive, and have tried looking at all the bug
reports etc and find the only workaround is changing sdx to hdx and that
im not gonna try

[William Walter Kinghorn]

Hi Miles, All,

I think all HDs are called sdx now days

Look here https://bugs.launchpad.net/ubuntu/+bug/97274
"I see now that changes from hda to sda is intended for kernels >=2.6.19"

Which points to : http://kernelnewbies.org/Linux_2_6_19#head-cdcbaa9c1b476decdc064e0a75d23d1328b1ddce
"Drives appear as /dev/sda, /dev/sr0, the old devices names won't work. You will need to change your boot parameters and your /etc/fstab parameters in order to get a working system with the new drivers. Again, this only happens if you use the new drivers, the old drivers continue working as they did before."

Hope this helps
William

________________________________________
From: linux-...@googlegroups.com [linux-...@googlegroups.com] On Behalf Of Miles [msdom...@gmail.com]
Sent: 08 February 2012 08:51
To: linux-studies
Subject: [lpi] Lets start

sudo hdparm -d /dev/sda

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[Linux Studies Group - http://groups.google.com/group/linux-studies/about]

"This e-mail is subject to our Disclaimer, to view click http://www.dut.ac.za/pages/22414"

[William Walter Kinghorn]

Hi Miles, All,

Look here : http://wiki.answers.com/Q/What_is_the_difference_between_sda_and_hda_in_Linux

William
________________________________________
From: linux-...@googlegroups.com [linux-...@googlegroups.com] On Behalf Of Miles [msdom...@gmail.com]
Sent: 08 February 2012 08:51
To: linux-studies
Subject: [lpi] Lets start

DMA is automatically configured by the operating system for most

sudo hdparm -d /dev/sda

[Miles]

Thanks William, You are in Durbs hey?
Hope to see you at one of our classes.
Miles