kvalobs=# VACUUM;
NOTICE:  number of page slots needed (157248) exceeds max_fsm_pages (153600)
HINT:  Consider increasing the configuration parameter "max_fsm_pages" to a value over 157248.
VACUUM
kvalobs=# 

The value may be updated in “postgresql.conf” and the postgresql server is restarted.

e.g. /etc/postgresql/8.3/kvalobs/postgresql.conf