| I appreciate the fact that you want to help the customer. But,
do you like to live dangerously. Making a sizing recommendation
for another vendor's software, especially the Big O, is not
the kind of position I would put myself in.
If you do recommend a solution, is Digital responsible if the
configuration doesn't perform? Are we responsible to supply
hardware until it does work? It may seem the right thing to
help out, but be wary of what your customer expects.
I've seen it happen many times, so be careful...
|
| Hmmmm ... 1.5 gb isn't very big for 250 users. So, I assume they
are hitting the same tables frequently and that, perhaps, the
application is mainly read intensive. Since you didn't specify
if the customer is using SQL*forms or not, I'll try to help in
both cases.
SQL*forms w/ 250 Users
----------------------
I had talked to Oracle several times the past few years on how to size
SQL*forms, number of users per VUP. As you would imagine, the numbers
are all over the place. However, two numbers *seemed* to appear more
than others. They are 3 and 7. So, if you use 3 per VUP, you need
at least a 9000-420 (250 / 3 = 83 vups). If you use 7 per VUP, you
need at least a 9000-410 or a 6000-460.
You must, under all circumstances, make Oracle give this number. Then
you can watch Oracle tell the customer that a Sequent S81 will support
250 users and watch the order slowly fade into the sunset !! To gain
additional insight to users/vup, call Mark Silverberg and ask him to
discuss his experiences with Oracle's SQL*forms performance.
Something Else (ACMS/DECforms/Oracle) w/250 Users
-------------------------------------------------
Since this is a small database, you may be able to draw some
comparisons between our TPCA work. Now, if you assume that the Oracle
database produces the same cpu and disk load, AND if you assume the
use of ACMS/DECforms; you could project a dual host 4000 or a single
6000-420.
The VAX 4000 has been clocked at 21.7 tps with 220 terminals being
threaded through various front-end uVAXes. If you add another 4000
to replace the multiple uV3100 used as front-ends, this would tend to
match. But, this dual host configuration would put you too close to
the edge so I would opt for the 6000-420 or the safer bet, the
6000-430.
This option would required the use of ACMS/DECforms and, yes, would be
a cluster. However, Oracle would only run on the backup 4000 (and
would only be licensed there too). If your customer is smart, they'll
look at the ACMS option carefully since it is obviously a better
solution for the ultimate end-user AND point rather dramatically to the
lack of an oltp strategy in Oracle's product line. Finally, if your
customer is really smart, they'll realize that Rdb is a much better
solution for the back-end too !!
I tend to agree with .1, but you probably need to help manage the
dialogue if you want to preserve the hardware.
-- gerry
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