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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