Hi,

I am currently Mirroring two 60GB drives on an important system, and I want to try to boost I/O performance by using a hardware RAID solution (instead of software driven md).

Any experience or ideas would be helpful. Because this system runs a production Oracle Database, I need to stay on RedHat 7.x. Good news, the Kernel is 2.4.20.

Any discussion or ideas would be appreciated.

Thanks,
GAVol

Have you had a look at the ATA RAID products offered by

http://www.promise.COM

and

http://www.adaptec.COM

And for serious data storage, should you not be using SCSI disks anyways?

No doubt you have heard that IBM has advised that some of their IDE Deskstar disks which are now failing at an unanticipated rate,
should not in fact be left running in 24h operation.

And do not forget the maxim that for IDE controllers, only connect one disk (as master) for each controller, since adding a slave greatly reduces performance!

I was not able to find an Adaptec Card with drivers (these things are still pretty new) - BUT the promise "FASTTRAK TX2000" (ATA133-RAID 0,1,10) card reports to support RedHat 7.x off the rack (drivers included). Thanks for the pointer. I ordered it today, and hope to get it here by next week...
...I will try to remember to ammend this thread when I get the TX2000 card and install it.

SCSI is great for serious storage, but I really can't afford the 15,000 RPM drives anyway - and the 7200 RPM IDEs are mirrored for the very issue of reliability. I've never had a problem with Seagate drives though - I'm running dual "ST340014A" drives. Once I get this on Hardware RAID, it will free up some of my CPU to deal with Oracle transactions (and cool screensavers).

Have a look at 3ware.

Interesting.

How do the 3ware products compare to the Promise products in terms of performance, pricing, and availability?

3ware are hardware RAID controllers. I don't think the Promise TX2000 is a hardware RAID controller because it doesn't look like it has any RAM chips.

I never bought 3ware products. I just drool over the features of 3ware products.

If 3ware has better RAID controllers AND Linux support, I may return the Promise card before I open it, and move up.

I do not have the Promise card yet - but if I find out that it's no better than the onboard IDE controller with software RAID, I will be very unhappy.

This confirms Electro's suspicions.

http://archive.lug.boulder.co.us/bym.../msg00067.html

I put in an RMA for the Promise TX2000 card and am now getting a 3ware 7000-2 card. The price difference is actually very small concerning the hardware support.for RAID controlling. ($20 difference) -- CDW Corporate TX2000 US$95 - The 3ware 7000-2 US$114. I'm trusing you guys here.

Thanks for the info!

Well I hope you did a Google search :+)

I did not know or realize that the Promise cards were only software RAID.
I am in fact using a Promise ATA 100 controller card (not with RAID feature) to support two ATA-100 IBM Deskstar drives on a motherboard which only had ATA-33 controllers and it has worked as expected and without any problems (both under Windoze 98SE and GNU/Debian Linux,
the machine being dual boot).

If you actually go back to the Promise site and read VERY CAREFULLY
what they say, it does become clear that their cards provide the controllers
but nowhere do they actually say that the RAID is being done in hardware.
It is a little deceptive, in that if you think as I did that as they are termed RAID cards it implies hardware RAID, but in fact is not, and they do not actually claim anything which they are not doing.

From the various items which came from doing a Gogle search (again which you should have done, and would have found the comparison of the Promise Card against the equivalent 3Ware card just using the promise card model keywords) the results indicate a very favorable report for the 3ware product.

So we have all learnt something from your initial question and I hope you
will provide a report on ease of installation and performance once you
get the card installed.

And something else that I should have thought to check, and in future
if you have any questions about kernel support for a particular device,
look first of all in

/usr/src/linux/Documentation/Configure.help

And here is the entry (found with greg -i 3ware Configure.help)

3ware Hardware ATA-RAID support
CONFIG_BLK_DEV_3W_XXXX_RAID
3ware is the only hardware ATA-Raid product in Linux to date.
This card is 2,4, or 8 channel master mode support only.
SCSI support required!!!

<http://www.3ware.com/>

Please read the comments at the top of
<file:drivers/scsi/3w-xxxx.c>.

If you want to compile the driver as a module ( = code which can be
inserted in and removed from the running kernel whenever you want),
say M here and read <fileocumentation/modules.txt>. The module
will be called 3w-xxxx.o.

So there should not be any problems about getting the card working
with a linux driver module.

And just before you panic about the comment about SCSI support,
that is not talking about physical SCSI devices, but having generic
SCSI support in the kernel, as you do with IDE cd-rewriters.