Database Load & Server Specs

Hi all,
I have three questions, would appreciate if any of you can help me on that, its important because I need these answers to support my claim of our server being over loaded.

First is; is there query to find out the number of transactions at any time? V$transaction tells about the time the query has been running for, but how many transactions are running at peak time? Does the number of transaction have any bearing on what the server specification should be like?

Second; what should be the specifications of a server, based on the size of the database or load? Are there any norms for this, or a matrix, which would help me see the specs based on load, or if any of you can share your experience?
(Our environment is OLTP, round the clock, 24x7, size of the physical
database is 15GB, and growing and the actual dump size is less though, around 5GB. We are using only one server, single processor 933MHz, 896MB ram, and 2 SCSI hard drives. Our application is module based, and since we made part of our last module online, the load has increased tremendously as it involves constant entry, reporting, and on screen viewing. I mean on WinNT, the CPU usage touches (for a few seconds thankfully) 100% every minute or two, which does make the system go a little slow every now and then.
If the configuration seems ok, which parameters can I consider revising/increasing to enhance performance?)

Third; since our is a critical hospital application, 24x7 environment, running on one server, with periodic Tape backups and one standby database, as our means to fall back on. Does that sound Ok? Or do we need a couple of servers, same specs, go for operating system clustering, with a storage unit housing a few Hard disks?

I know it's a very long query, but would really appreciate if I can have some guidelines.

Thanks and regards,

Hussain
DBA SKMCH&RC

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Please see the official ORACLE-L FAQ: http://www.orafaq.net
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Author: Hussain Ahmed Qadri
  INET: hussain_at_skm.org.pk

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