Some PostgreSQL configuration parameters can only be changed by "reloading" the whole configuration file.
On all platforms, there is a specific command to reload the server, which is as follows:
UBUNTU/DEBIAN pg_ctlcluster 9.0 main reload RED HAT/FEDORA service postgresql reload pg_ctl -D /var/lib/pgsql/data reload SOLARIS pg_ctl -D /var/lib/pgsql/data reload MAC OS pg_ctl -D /var/lib/pgsql/data reload FREEBSD pg_ctl -D /var/lib/pgsql/data reload
You can also reload the configuration files while still connected to PostgreSQL. This can be done from the command line as follows, if you are a superuser:
postgres=# select pg_reload_conf(); pg_reload_conf ---------------- t
which is also often ...