On Wed, Aug 27, 2003 at 11:04:03PM -0700, Bryan Vyhmeister wrote:
  | I have recently built a single Xeon 2.4 GHz system based on a Supermicro
  | X5SS8 motherboard along with an Adaptec 2010S Zero Channel Raid card. I
  | am using two Seagate 36 GB, 10,000 RPM, Ultra320 SCSI hard drives in a
  | RAID 1 setup. I have 1GB of ECC DDR RAM installed.

If you have a spare modern-ish IDE drive, try using that and compare
against the 2010S.

In my experience, the 2400A and 2100S cards don't have great
sequential throughput in RAID-1, and I've seen various articles
indicating that others have noticed that.  If the 2010S is based
on a similar CPU and firmware as the 2100S, it may have the same
"lame RAID-1 performance issues".

(To put this in perspective, I was getting ~ 40MB/s sequential on a
single drive on a 2400A, and when I mirrored that drive it dropped to
10MB/s).

That all said, with 1GB of RAM you shouldn't be hitting the disk
that much, compiles are more IO/s bound than sequential throughput
bound, and the 2400A/2100S are quite good for IO/s in a RAID-1
configuration.


  | Has anyone else observed similar issues on a Xeon system? I am really
  | not sure what to think. It seems very strange.

We've got a build host that's a dual Xeon 2.8GHz with 2GB of RAM and
a couple of IDE disks software mirrored with RAIDframe, and it is
very very zippy.