Why is 9i pausing?

Hi all,

I'm experiencing an intermittent performance problem reading and
writing a 9i database from Sqlplus. I'm running Sqlplus on my laptop
and the DB is on a Sun box in the same office. It seems that if my
connection to the DB is inactive for a period of time, there is usually
a really bad lag when next I try to read or write the DB. If I do a few
things in quick succession, they all seem to execute reasonably
quickly. Whether a period of inactivity forces Oracle to go through
some sort of extended handshaking when activity picks up again, I don't
know, but that's what it feels like to me.

In my read tests, the data - once it starts to stream - comes back at a
decent rate, but there's sometimes a delay of upto a minute before it
starts to send. I got a similar result with write tests: I created 1000
rows in next to no time but when I tried it a second time, there was a
pause of about a minute before it started, then it created the 1000
rows pretty quickly.

FWIW the Sun box has 1.5GB memory, is serving a total of three 9i
databases, and is inactive apart from the tests I'm doing. My database
is running on default instance parameters (it was created as a "new
database" in DBCA, and I just accepted all the defaults).

I'm stuck! Any ideas what is causing the pause?

TIA
Tarby

Sybrand,

Fine - I'm sure that someone else will be prepared to at least give me
some pointers. I'm not planning paying any consultants to look at the
problem, so folks needn't feel guilty about helping me out...

For anyone who *is* willing to offer advice: according to Enterprise
Mgr Console, the total SGA size is 130MB in each DB, so perhaps the
swapping isn't that big an issue. There is some swapping, sure, but the
Sun box isn't permanently on it's knees - the problem is intermittent
and SAR reports that the box is pretty much idle. Sometimes data is
written & read at a perfectly acceptable speed, other times there's the
pause I referred to before Oracle does anything, and this pause often
comes when I execute a statement after a period of inactivity.

TIA
Tarby