Re: Users per MTS Ora 9

> If I understand your post right, that means you don't have MTS at all.
With
> no shared server processes, and unless you specifically state
> (SERVER=SHARED) in your tnsnames.ora, then each user gets a dedicated
server
> process. No wonder the 8.1.7 database performed so well!

If you have MTS configured, then new sessions get a shared server by default. They get dedicated only when server=dedicated is set in tnsnames.ora.

> If you have lots of jobs that last longer than about 3 seconds, then you
> shouldn't be using MTS. Long jobs means the job hijacks the shared server
> process for a long time... which means fewer shared server processes for
> other users. MTS is only really of benefit in an environment where most of
> your server process time is spent idle, waiting for a user to do the next
> piece of SQL. If you have long-running SQL, then your server processes are
> spending most of their time doing long-running SQL!

I generally agree with you, but where does this 3 seconds come from? I'd put the need for MTS dependent on amount of server processes idle time and free system memory.
If you got enough memory, you can very well go all the way with dedicated servers (other issues, as max number of OS processes are minor in most systems). But if you don't have lots of extra memory, and if some of your server processes have idle time, you could reduce the number of them and use MTS for sharing them between sessions.

Tanel. Received on Sat Jun 28 2003 - 12:03:43 CDT