The CONNECTIONS parameter at 9.3+ reflects both application server and Direct Connect
conections. I've yet to be able to convince a Windows host to accept more than ~117
application server connections without running out of non-interactive desktop heap (I ran
equivalent Linux hardware to 400 application connections in a fraction of the time), so I'll
assume you're mostly using Direct Connect. It's really up to the database on how many
connections to accept, and the server host to perform adequately under load.
You will hit a limit at some point, and it will likely become obvious when you do; unfortunately,
there may not be much warning before performance goes into a death spiral. For the meantime,
you can keep an eye on things by establishing an evaluation test to be done weekly, during a
point in time where the system is under "normal" load, which captures both number of connected
users and the time to accomplish a medium difficulty process; it's easier to justify infrastructure
improvements when you have data to back up your request.
- V
