Constant file growth.

Hello

    I have noticed that my postgresql database sees a constant growth to some of
the system files:

184M    17112
Database=# select relname from pg_class where relfilenode = 17112;
             relname
---------------------------------
 pg_attribute_relid_attnam_index
(1 row)

 77M    17115
Database=# select relname from pg_class where relfilenode = 17115;
             relname
---------------------------------
 pg_attribute_relid_attnum_index
(1 row)

 44M    17121
Database=# select relname from pg_class where relfilenode = 17121;
        relname
------------------------
 pg_class_relname_index
(1 row)

    These files represent 305M out of the 454M of my database. Any hints on why
it is so and how I can fix it would be greatly appreciated. Dropping and
reloading is next to useless. I am using 7.1.3 under FreeBSD 4.3.

Alex