CentOS - Aug 2009 - Slow IDE on GeForce 8200 board

In my haste for help, I stupidly hit reply and changed the subject which I
thought was enough for a new message, not giving much thought for the threading,
etc. So apologies for the hijack, although I would think it fairly obvious that
it wasn't deliberate or obvious to me... or a big deal really. My mail
doesn't thread.

Some further info for those actually interested in helping, I forgot that the HD
in question had an Ubuntu 8.10 install on it, so I fired that up and hdparm -t
produced 56MB/Sec. So the issue is either kernel or config.

Thanks for your patience.

----- Forwarded Message ----




I
have a system who's normal activity is running Xen 3.3.1 with Centos
5.3 as the DomU. I had reason to connect an IDE drive to the single IDE
interface that this board has. I was getting slow performance. hdparm
-t revealed that the thoughput was down to just 2.7 MB/sec. After some
tweaking (switch on 32 bit,etc) and retesting under a non-Xen config, I
managed to get that to 8MB/Sec. When I move the drive to a USB to IDE
adapter, hdparm -t gives me about 18MB/Sec. Big improvement, although I
don't know if it is then perfect..



My kernel is
2.6.18-128.4.1.el5. I have kernel parameter pci=nomsi. I can't remember
exactly why I needed this, but there was a good reason, maybe SATA
drive not working properly or some such. Could this be the cause of my
issue?

The
motherboard blurb states that the IDE interface is ATA/133 compliant
and I am using the provided IDE cable. I have tried three hard disks,
all with similar results. (2x 40gb + 1x 160gb)

lspci | grep IDE gives
00:06.0 IDE interface: nVidia Corporation MCP78S [GeForce 8200] IDE (rev a1) 

As a reference, hdparm -t against the SATA drive in AHCI mode on the same board
gives about 110MB/Sec.

Any ideas, anyone?

Thanks in advance,

Ian.



      
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2009/8/11 Ian Murray <murrayie at yahoo.co.uk>:
> In my haste for help, I stupidly hit reply and changed the subject which I
> thought was enough for a new message, not giving much thought for the
> threading, etc. So apologies for the hijack, although I would think it
> fairly obvious that it wasn't deliberate or obvious to me... or a big
deal
> really. My mail doesn't thread.
>
> Some further info for those actually interested in helping, I forgot that
> the HD in question had an Ubuntu 8.10 install on it, so I fired that up and
> hdparm -t produced 56MB/Sec. So the issue is either kernel or config.
Check if ultradma and unmasq interrupts flags are set(both under
ubuntu and centos):

hdparm -u -d /dev/hda