"Pascal PEYRE" <peyre@cir.fr> writes:
> I have some big postgreSQL databases (4/5 GB at start) on this server.
> Every night I erase data and I import a lot of new data.
Exactly how do you erase the old data? If you're zapping the entire
contents of tables, TRUNCATE might be a good answer.
> For optimize my database I operate a vacuum "all" every night.
Plain vacuum, or vacuum full? If it's a plain vacuum, do you have the
free space map parameters (in postgresql.conf) set large enough to cover
your database?
> The problem is that the size of database is growing every day whereas
> the volume of data stay remains stable.
Exactly which tables are bloating? Look at the relpages column of
pg_class (just after a vacuum, so that the values are up to date).
Look to see which entries grow from day to day...
regards, tom lane