Performance

I'm having some problems achieving adequate performance from Postgres for a
real-time event logging application. The way I'm interfacing to the
database may be the problem:

I have simplified the problem down to a single (non-indexed) table with
about a half-dozen columns (int4, timestamp, varchar, etc.) I wrote a
quick and dirty C program which uses the libpq interface to INSERT records
into the table in real-time. The best performance I could achieve was on
the order of 15 inserts per second. What I need is something much closer
to 100 inserts per second.

I wanted to use a prepared SQL statement, but it turns out that Postgres
runs the query through the parser-planner-executor cycle on each iteration.
There is no way to prevent this.

The next thing I though of doing was to "bulk load" several records in one
INSERT through the use of array processing. Do any of the Postgres
interfaces support this? (by arrays, I don't mean array columns in the
table).

I'm currently running Postgres 6.4.2. I've heard that 6.5 has improved
performance; does anyone have any idea what the performance improvement is
like?

Is it unrealistic to expect Postgres to insert on the order of 100 records
per second on a Pentium 400 MHz/SCSI class machine running Linux? (Solaris
on a comparable platform has about 1/2 the performance)

Thanks in advance...

Steven Bradley
Lawrence Livermore National Laboratory
sbradley(at)llnl(dot)gov