slow disk in fedora 6 / hda sda detection issue

tarik · 09-07-2007, 06:14 AM

Please would anybody be able to help me improve the performance of a fedora 6 HP DL140 server...

I'm having serious issues with its disk speed, which is causing a huge bottleneck on the network.

Quote:

# hdparm -t /dev/hda
/dev/hda:
Timing buffered disk reads: 12 MB in 3.59 seconds = 3.34 MB/sec

After reading in some forums, I attempted to set DMA to 1 for this disk hoping that it might improve the situation, though I receive the following error:

Quote:

# hdparm -d1 /dev/hda
/dev/hda:
setting using_dma to 1 (on)
HDIO_SET_DMA failed: Operation not permitted
using_dma = 0 (off)

Q. Is there any way in Fedora 6 that I can enable this feature?
Ideally I'm looking for a modprobe line, or something which I can at least test from the command line, as I'm working on this machine remotely and have no kvm access.

To add to my confusion, the output of hdparm -i /dev/hda reveals Model=ST3808110AS

Google confirmed my suspicion that this model is fact a SATA drive:
Seagate Baracuda 7200.9 80GB 7.2K SATA Hard Drive

As far as I understood linux will identify sata drives as sda rather than hda, though unfortunately as the server is now racked I cant just open it up and take a look at whether it is actually using SATA or IDE.

So I am wondering whether this issue is deeper than simply that DMA needs to be enabled - is it possible that fedora could be mistaking the SATA drive for an IDE drive?

Here is some output from /var/log/messages on startup:

Quote:

Sep 6 12:39:18 cherry kernel: Uniform Multi-Platform E-IDE driver Revision: 7.00alpha2
Sep 6 12:39:18 cherry kernel: ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
Sep 6 12:39:18 cherry kernel: hda: ST3808110AS, ATA DISK drive
Sep 6 12:39:18 cherry kernel: ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
Sep 6 12:39:18 cherry kernel: hda: max request size: 512KiB
Sep 6 12:39:18 cherry kernel: hda: 156301488 sectors (80026 MB) w/8192KiB Cache, CHS=16383/255/63
Sep 6 12:39:18 cherry kernel: hda: cache flushes supported
Sep 6 12:39:18 cherry kernel: hda: hda1 hda2 hda3

And some other specs which may be helpful:

Machine hardware: HP ProLiant DL140 G3
# uname -r: 2.6.22.2-42.fc6

lspci shows:

Quote:

00:1f.2 IDE interface: Intel Corporation 631xESB/632xESB/3100 Chipset SATA Storage Controller IDE (rev 09)

If anybody has any ideas please let me know as I need to get this fixed asap and am already starting to lose sleep over it!

Thank you!

Electro · 09-07-2007, 11:38 PM

Seagate SATA hard drives are known to have problems enabling DMA in Linux because of hard drive and controller conflict. I suggest change the hard drive with a different brand. Though you can try to add hda=dma to the bootloader and/or add noapic to the line.

I suggest Western Digital 'Raptor' 72 GB will be a good and reliable replacement.

Intel can change its SATA connections to emulate like a PATA to ease installing operating systems like Linux.

Try installing lshw to get a list of hardware that is in the server.

tarik · 09-10-2007, 06:07 AM

Thanks Electro.

lshw seems to reveal that the disk is using the ata_piix driver...

Quote:

*-ide
description: IDE interface
product: 631xESB/632xESB/3100 Chipset SATA Storage Controller IDE
vendor: Intel Corporation
physical id: 1f.2
bus info: pci@0000:00:1f.2
version: 09
width: 32 bits
clock: 66MHz
capabilities: ide pm bus_master cap_list
configuration: driver=ata_piix latency=0 module=ata_piix

*-ide
description: IDE Channel 0
physical id: 0
bus info: ide@0
logical name: ide0
*-disk
description: ATA Disk
product: ST3808110AS
vendor: Seagate
physical id: 0
bus info: ide@0.0
logical name: /dev/hda
version: 3.AJJ
serial: 5LRBZ302
size: 74GB
capacity: 74GB
capabilities: ata dma lba iordy smart pm partitioned partitioned:dos
configuration: smart=on
*-volume:0
description: Linux filesystem partition
physical id: 1
bus info: ide@0.0,1
logical name: /dev/hda1
capacity: 196MB
capabilities: primary bootable
*-volume:1
description: Linux swap / Solaris partition
physical id: 2
bus info: ide@0.0,2
logical name: /dev/hda2
capacity: 2000MB
capabilities: primary nofs
*-volume:2
description: Linux filesystem partition
physical id: 3
bus info: ide@0.0,3
logical name: /dev/hda3
capacity: 72GB
capabilities: primary

... which baffles me as I had come to the conclusion that it was using the generic ide driver and that if I added hda=noprobe and hda=none into grub.conf it would switch to the ata_piix driver, appear as sda, and fix the problem.

Here's some text I found whilst looking around on the subject:

Quote:

In recent Linux kernels, there are two modules capable of handling the ICH6 disk controller:

* ata_piix: the disk shows as /dev/sda and DMA is enabled.
* Generic IDE driver (ide-disk): the disk shows as /dev/hda and DMA is disabled.

The simplest way to enable DMA is to force the IDE driver to ignore the system hard disk by passing the hda=noprobe and hda=none kernel argument. The driver will then be handled by the ata_piix driver. Note that this will change its device name to /dev/sda (which may require changes in /etc/fstab and the boot loader) and may cause other problems as listed above.

I have also been discussing this here:
http://forums.fedoraforum.org/showth...286#post861286

When you say..
"Intel can change its SATA connections to emulate like a PATA to ease installing operating systems like Linux."

.. is this what you think is happening in this case - why it's showing as hda instead of sda, or are you suggesting that there is something i can do?

If you are able to shed any light on what's going on here I would appreciate it! thanks for your help.