"Evert Daman" <e.daman@wanadoo.nl> writes:
> we had never used the vacuum before (database was up
> for about two months). after doing that too things were
> speeding up again. but that couldn't be the cause of the
> lost user could it?
It could be, if you'd managed to execute 2 billion transactions in
two months ... which seems a bit implausible. But in any case,
please read the documentation about required routine maintenance.
regards, tom lane