[LUNI] experience with 3ware

[Martin Maney]

On Thu, Mar 14, 2002 at 03:42:31AM -0600, Rick Sullivan wrote:
> I experienced the same thing (88% cpu util with an Athlon MP 1600+ and
> 512 MB RAM on NT4 SP6a) a couple of weeks ago on an Abit KG-7 RAID,
> which has the HPT370 chip - RAID 10 with 2 IBM 60GX 40 MB drives. So
> these are just general feelings, and thruput was not measured. The
> thruput of the IBM 60 GX drives is no more than a current 10K RPM SCSI,
> which is what the first test was compared against (I think
> StorageReview,com had an article about this in the last 6 months), so I
> would expect CPU util would be somewhat closer to the 15% of SCSI. One

If I understand you, there wasn't anything the same, so the CPU usage
figures are bascially meaningless.  Not that I actually doubt that the IDE
solution might not use more of the CPU than the much more expensive SCSI
RAID controller, but between the apples on one side and watermelons on the
other, well, it's just not a very useful guide, is it?

> more complicating factor is the 3Ware is a much better RAID controller
> than the HPT370.

I may be wrong, but I thought the HPT was one of those currently popular
"Win-RAID" chipsets - not really hardware RAID, just a UDMA controller
that's bundled with (Windows) software RAID.

> It's certainly not an issue if the box is being a file server. But if it
> were a SQL server under heavy load ... ???

It would depend, wouldn't it?  Simple SQL queries are almost certainly
disk-bound on any remotely current CPU.  For less simple job streams it's
less easy to say without actually trying it, eh?

-- 
You arguably have quite a few inalienable rights,
but being taken seriously isn't one of them.
Neither is being respected.  -- Rick Moen  <linuxmafia.com/~rick/faq/>