Linux Hardware: 3Ware 9650SX with Linux. (tummy.com, ltd. Journal Entry)
tummy.com: we do linux

Saturday October 06, 2007 at 16:45
Subject: Linux Hardware: 3Ware 9650SX with Linux.
Keywords: Hardware, Technical
Posted by: Sean Reifschneider

A client recently purchased a couple of new systems with PCI-E instead of PCI-X (AKA 64-bit PCI, the old standard PCI but in a longer slot). The 3Ware PCI-E board is the new 9650SX. However, this board is only supported by the drivers in the 2.6.19 and later kernels. Read on for more information about using this board with Linux and especially Debian Etch.

This client is using Debian Etch, but the stock install disc for Etch, as well as CentOS 5, uses 2.6.18 without a back-ported driver for this board. 3Ware supplies an updated Etch CD, but this CD includes many updated packages above what the stock Etch CD provides, and also uses an apt.sources file which references Debian release "lenny". In other words, using the 3Ware supplied CD will not result in the same installed bits as a stock Etch CD, particularly if you answer "yes" to the "use network installation source" installer question.

Saying "no" will cause it to install just from the CD, but there are many updated packages on the CD. So installing from the CD and then changing the source from "lenny" to "etch" and doing an upgrade is a better option, but still not exactly what you would get from a stock Etch install disc.

We looked briefly at building a custom install disc, but after a couple of hours with many failed attempts, we decided to abandon this route. Instead we added another hard drive to the system's on-board controller and did:

  • Install to the hard drive on the supported controller.
  • Upgrade to the backports 2.6.22 kernel.
  • Reboot into the 2.6.22 kernel.
  • Copy the disc we installed on into the array.
  • Make the array bootable.
  • Remove the drive from the supported controller and reboot on the array.

Then we could just use the stand-alone hard drive to install the other systems that had the same configuration. Actually pretty nice since we'd gone through a system install work-flow and gotten a bunch of system configuration work done on the master disc before installing the others.

Of course, another option would have been to tar up the "install hard drive" and use the 3Ware provided CD to boot up and format the array for installation. However, the environment on the CD is more minimal so it's trickier to get it all working.

Just a few tips for those looking at the 3Ware 9650SX. I, personally, have been avoiding them in preference for the 9550SX PCI-X card which I know works. So I select systems with PCI-X over PCI-E, and expect to do so as much as possible for the next year or so until at least CentOS has an install disc with the drivers on it, and probably Ubuntu LTS also is in the same position.
(Post Reply)

Comment
Nat Makarevitch
Subject: Performances?
Are you happy with the performances on random I/O? Writes? iowaits?

I had a 9550 and was very unhappy (140 random IOPS on a 6-drives RAID5!), just traded it for a 9650 which is now under test (see http://www.makarevitch.org/rant/3ware/ )

Comment
Author: Sean Reifschneider
Subject: Seems fine.
It seems fine. It's not great, but I wouldn't call it particularly slow either. Though I haven't really measured it, I just use it. I do know that in the "safe" mode it is very slow. I set it for "balanced" and it seems fine with a BBU. I would agree that it's not up to the performance of the marketing claims 3ware makes, but it's a rock solid product under Linux and that's worth some performance to me.

Sean