[SunRescue] recommendations: IPX or SS-2?

[James Lockwood]

On Thu, 3 Feb 2000, Gregory Leblanc wrote:

> This is kind of silly.  7200RPM drives are not inherently hotter than
> 5400RPM drives.  If you look at the first 5400RPM drives that came out, such

Yes, they are.  All other things being equal, frictional losses increase
with rotational speed due to shear forces on the bearing contact.  In the
case of lubricated bearings, you are introducing turbulence at the boundry
layers.

Now, all other things are not always equal.  There have been substantial
advancements made in bearing technology (such as the upcoming air bearing
drives) and this has helped substantially.

> as some of the early Seagate HAWK drives, they are just as hot as the early
> 7200RPM drives.  If you compare some of the 5400RPM drives made 2 years
> later to the 7200RPM drives made two years after that speed was introduced,
> they're pretty close to the same running temperature.  Heat reductions are

Compare the heat output and cooling requirements for a first generation
Seagate Hawk (5400RPM) with a first gen Barracuda (7200RPM) and you notice
major differences.  Technology has pushed temperatures down across the
board but faster drives will always be hotter at the same technological
level.

My reason for not wanting to put faster disks in an IPX or SS2 is simple
economics.  The onboard SCSI bus won't go faster than 5MB/sec no matter
what you do, and that's pushing it.  Why shell out more bucks for a faster
drive when it will make no difference?

Then again, my main home storage is a 12-way stripe of differential
Elite-9's.  Not cool or quiet running by any means.  That and they bring
my UPS to its knees.

-James