My guess is that they are all 7200 RPM drives (they all are on
my systems.) I once found the exact model # and looked up our 9GB
drives on a Seagate web page and they were pretty much normal
performance (for 3 year old drives) with 7-8ms seek times. The 2gb
might be a tad slower, being older. But often 4 9GB older, slower
drives will outperform a very fast 36GB drives, if they are accessed
in parallel.

One thing many people forget is that the old 9x9 series
is limited by its PB bus speeds of 32mb a second.
So even the relatively slow (by today's standards) 20mb a second
Fast Wide SCSI cards can be limited by this. You can add more
bus expanders (in fact, have to if you add the 4 more slots available
inside the 979 chassis, and the external chassis also requires another
PB interface.)

I think the older 7200rpm drives are fairly well matched to the
existing I/O system. I note that when HP sells the HVD enclosure
for discs, they won't sell the 15,000rpm drives for the 9x9 series
( I assume because they are too fast.) Incidently, those 15,000
rpm drives have ultra fast seek times too.

For many applications, a single processor 979 will not be able
to fully drive that many discs and channels anyway (at least
based on my experience watching a 939, 989 and 979-200 with
various I/O configs. When I process large files with Suprtool
(which processes about as efficiently as possible) I note that
my 939 doesn't quite run at full speed but often pegs the cpu,
the HP979 is pretty balanced, and the HP989 can process it a
bit faster than the disc system can deliver it (with essentially
nothing else running.) If you start getting into multi-processors,
then you are more likely to be limited by the disc system and would
want more discs on more SCSI channels if you can do it.

Of course, everything depends on the application.
And if you don't have lots of memory, adding more will decrease
the load on your discs and make them seem faster.


-----Original Message-----
From: Stan Sieler [mailto:[log in to unmask]]
Sent: Thursday, May 24, 2001 1:40 PM
To: [log in to unmask]
Subject: Re: [HP3000-L] 979KS100 SERVER


Re:
> Can anyone help. Looking at my support contract, just renewed. The
979KS100
> has  Product# A3351A  4 ea  2GB SCSI-2 Disk Drive and  Product# A3312AZ
> 4ea  2x4.3GB FWD High Performance Disk Module. I would like to have the
> SPEC.S on the Hardware, The Average Seek Time, The Max Seek Time, The Data
> Transfer Rate, The Disk or Platter Size and the RPM''s.

Although you may be able to find the *specs* at HP's or Seagate's
(or whoever's) web site, that doesn't mean that the drives are living
up to their specs ... nor do the specs tell you what you're going to
get on a particular system (especially transfer rate).

What's the model number of the drives (not the HASS box)?

<plug>
DiskPerf, from Allegro Consultants, Inc., can measure the actual
performance you can get from your disk drives.

Info at: http://www.allegro.com/products/diskperf/
</plug>

Stan Sieler                                           [log in to unmask]

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