topic Re: DL140 G2 SATA disk speed in Operating System - Linux

DL140 G2 SATA disk speed

Richard Allen — Fri, 07 Oct 2005 11:05:08 GMT

I just setup a DL140 G2 (375589-421) with Red Hat Enterprise Linux v4 Update 2.

I'm getting very poor performance on the disk drives, less than 3 MB per second.

I ran "hdparm /dev/hda" and notice that "using_dma" is not set and cannot be set (hdparm -d1 /dev/hda) with error "Operation not permitted".

This server comes up as a supported system on the HP web which seems odd to me if it's performing so badly.

Re: DL140 G2 SATA disk speed

NiCK_76 — Sat, 08 Oct 2005 02:00:30 GMT

Hi Allen ,

Do you use SATA harddrive? or SCSI harddrive?

I suggest you use 2 method to benchmark i/o performance.

1, perform command "time dd if=/dev/zero of=/aaa bs=1024k count=3000", in the same time and another console perform command "vmstat 1 10000" to gather infomation.

2, perform command "time tar cf directory(i use redhat 4 discs)" to have a try. And in the same time and another console perform command "vmstat 1 10000" to gather infomation.

Put on below result.

NiCK

Re: DL140 G2 SATA disk speed

Stenuit Jean-François — Fri, 14 Oct 2005 13:34:17 GMT

Same symptoms down here.

This seem to be related to the fact that the linux kernel recognise the drive as an old Parallel-ATA drive.

My guess is that there is an emulation layer in HP's bios that should be removed so that the linux kernel recognise the drive as a SATA one.

You can see wether you are using the old PATA driver if your device is named /dev/hda. It will be /dev/sda if you are using the SATA driver.

Re: DL140 G2 SATA disk speed

Richard Allen — Tue, 18 Oct 2005 10:35:45 GMT

This is in fact the problem (SATA disks detected as /dev/hd*). I think I have most likely ruled out a hardware problem since I got another DL140 G2 and with the same symptoms.

The clock seems to stop now and then, the hard disks become unavailable for extended periods when handling high IO loads.

Re: DL140 G2 SATA disk speed

nikoz — Sun, 06 Nov 2005 09:31:31 GMT

I found i stupid mistake since kernel 2.6 no problem sata reconition if you have any cd driver on ide adapter mounted.
so if you have a cd driver inside your hd is sda and/or sdb if you dont have they becames hda/hdb .
The problem is only bios emulation so let hp repair this stupid problem!!!!!

Re: DL140 G2 SATA disk speed

Richard Allen — Sun, 06 Nov 2005 20:05:07 GMT

I have found that this problem can be addressed with having a IDE CD-ROM hooked up to the machine.

https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=172301

Re: DL140 G2 SATA disk speed

Dan Tucny — Wed, 30 Nov 2005 08:09:20 GMT

A workaround to this problem is to change /boot/grub/grub.conf and specify 'ide0=noprobe ide1=noprobe' on the 'kernel' lines as follows.

Change...
kernel /vmlinuz-2.6.9-22.0.1.EL ro root=/dev/VolGroup00/LogVol00
...to...
kernel /vmlinuz-2.6.9-22.0.1.EL ro root=/dev/VolGroup00/LogVol00 ide0=noprobe ide1=noprobe
...

Subsequent kernel installs will also get these additional parameters, so this doesn't need to be redone later.

When this change has been made and the system rebooted, your hard disk will now be /dev/sda not /dev/hda and performance will be a lot faster.

This doesn't affect the DL145 G2, only the DL140 G2...

I hope this helps...

Dan

Re: DL140 G2 SATA disk speed

Hoang Le_1 — Wed, 07 Dec 2005 15:28:56 GMT

I've got the same problem. Here is another strange behavior. The server is not able to boot from USB if no CD drive attached to the system. For some reason, with or without CD drive has dynamically changed the BIOS setting.
This is definitely HP problem.

Re: DL140 G2 SATA disk speed

joel flickinger_1 — Tue, 12 Sep 2006 14:22:49 GMT

So was this ever addressed by HP or did they just not bother? We have the same problem on about 15 machines and are about ready to send them back.

Re: DL140 G2 SATA disk speed

Richard Allen — Mon, 18 Sep 2006 06:11:58 GMT

My experience is that appending the following parameters to the kernel boot will rectify the problem:

ide0=noprobe ide1=noprobe

I don't agree that this is a HP problem but a kernel problem, the kernel is detecting them as non-SATA disks.