Re: Oracle sessions/proccesses

Thanks for your reply. That's reassuring to know - my manuals say when setting up the database to allow 7 processes for background tasks and 1 per user, but I was getting confused because it didn't seem to work that way in practice!

The reason for asking is we are licensed for 40 concurrent users and I was concerned that we may be (inadvertantly) exceeding that limit, as the max number of processes had been set to 100. From what you say, we may be ok.

The database is used mainly by application users, but also by users via odbc and asp scripts. The scripts connect only briefly, but the processes remain visible in instance manager for the 60 second default period. Does each connection take 1 license, and if so is that license taken for the entire time the process exists or just while the user is actually communicating with the database?

thanks for your help

Richard

"Howard J. Rogers" <hjr_at_dizwell.com> wrote in message news:<3f856bab$0$28120$afc38c87_at_news.optusnet.com.au>...
> Richard Stanton wrote:
>
> > Hello
> >
> > I am running Oracle 8.05 on nt.
> >
> >
> > Can anyone explain to me the relationship between Oracle sessions and
> > processes?
> >
> > Is it 1 connection to the database = 1 process?
>
> Not necessarily. Try doing a select * from sales parallel 8. One connection,
> 9 processes.
>
> That's just one example.
>
> The other way holds true as well. In multi-threaded server configurations,
> one hundred connections could be causing just a couple of processes to be
> used (dispatchers and shared server processes).
>
> >If so, then why in
> > Instance
> > Manager do the two not tally up? For example, there are currently 34
> > sessions listed - 26 from the application, 7 background and the
> > session I am using. However, when I switch to the Resource limit tab
> > it lists 35 sessions and 61 processes. So what are these extra
> > processes?
> >
>
> Are you using the Enterprise Manager console? Then the Intelligent Agent
> counts as another session. Just for starters.
>
> > We sometimes hit the max number of processes. What are the
> > implications to the database performance if I increase the limit,
> > currently set to 100?
>
> There are a lot of implications, because processes is one parameter that is
> used by others to determine their limits unless otherwise explicitly set.
> You'd have to trawl through tahiti.oracle.com, which contains a complete
> list of init.ora parameters, to find them all.
>
> >
> > Hope that all makes sense
> >
> > thanks
> >
> > Richard
>
> I've been a a bit vague in my reply, largely because it's just gone
> midnight. But there is no one-to-one correspondence between users, sessions
> and processes. It can get horribly complicated by things I'm sure you'll
> say you're not using, such as CMAN, MTS, the Intelligent Agent, Parallelism
> (explicit or implicit) and so on. Thing is, there's a lot of factos to
> affect the numbers. I wouldn't worry about whether the numbers tie up
> precisely, but I would be doing some research on the implication of
> increasing the processes parameter. You certainly don't want to set it to
> some ridiculous sky-high value, just a modest increase from what you've
> currently got, because obviously 100 is not sufficient.
>
> Regards
> HJR
Received on Fri Oct 10 2003 - 06:12:31 CDT