[comp.sys.dec] workstation I/O, scsi disks

lynch@theory.tn.cornell.edu (Tim Lynch) (10/15/90)

Hello,

My section is in the process of choosing a workstation that will
manage a very large database.  Over ten gigabytes.  We expect an average
user load of maybe 8 users.  Due to budget constraints, we must consider
a low-end workstation and will probably try to save additional monies by
purchasing third party SCSI disks to obtain the ten-plus gigabytes needed.
My questions have to do with disk I/O;  I hope someone can provide me
with some comparative data on DEC, Sun, and IBM workstations.  Sorry, I
don't have particular model numbers in mind, but we hope to keep
expenditures on the main box, without disks, under $25,000.

1.  Does anyone have any experience on performance of vendor-supplied
	vs. third-party SCSI disks on any of these machines?  Benchmarks?

2.  The October issue of "Unix Review" compared the IBM, Sun, and DEC
	machines among others.  The article included some charts on
	disk I/O with the IBM looking significantly better than the
	others.  Does any know to what extent that performance was the 
	result of driver/controller vs. the hard drive?  If we should 
	buy an IBM workstation and plug in third-party SCSI, do we loose
	this performance edge?

Thanks.  I'll summarize or respond via email to anyone asking for 
copies of what I learn.

Tim Lynch

pavlov@canisius.UUCP (Greg Pavlov) (10/18/90)

In article <1990Oct15.124629.23056@batcomputer.tn.cornell.edu>, lynch@theory.tn.cornell.edu (Tim Lynch) writes:
> 
> Hello,
> 
> My section is in the process of choosing a workstation that will
> manage a very large database.  Over ten gigabytes.  We expect an average
> user load of maybe 8 users.  Due to budget constraints, we must consider
> a low-end workstation and will probably try to save additional monies by
> purchasing third party SCSI disks to obtain the ten-plus gigabytes needed.
> My questions have to do with disk I/O;  I hope someone can provide me
> with some comparative data on DEC, Sun, and IBM workstations.  Sorry, I
> don't have particular model numbers in mind, but we hope to keep
> expenditures on the main box, without disks, under $25,000.
> 
  I don't know what your application is, but the implication of a 10+ gigabyte
  database is that you may want to be concerned about the quantity of memory
  you have available, down the road if not at the moment.  Taking that into
  account, while the IBM system gives you a lot of horsepower and theoretical-
  ly very good disk performance, I am not sure that your budget would allow
  you to go very much beyond the Model 320 which, I believe, has rather 
  limited memory expansion  (any expansion, for that matter) capability.

  Of the other two, we ran database-oriented benchmarks during the past year
  on both a DEC 5000 and a SUN 390, among other machines.  The former beat
  the latter by a good margin;  I would expect that the SUN 490 is comparable
  performance-wise to the 5000 (tho probably more expensive, no ?)

  There are several groups of people at Cornell who 1) have DEC 5000 systems
  and  2) have been experimenting with third party disks.  It seems that they
  should be able to provide you with some direct experience.

   greg pavlov, fstrf, amherst, ny

   pavlov@stewart.fstrf.org