Vacuum ALL FULL

Found a notice after completing the
vacuumdb -p 5433 -- all --analyze --full -v
max_fsm_relation = 1400 in postgresql.conf
Thou all our 50 db individually have less then 1400 relation , when it
completes , there was NOTICE that increase the max_fsm_relation.
INFO: free space map contains 10344 pages in 1400 relations
DETAIL: A total of 25000 page slots are in use (including overhead).
54304 page slots are required to track all free space.
Current limits are: 25000 page slots, 1400 relations, using 299 KB.
NOTICE: max_fsm_relations(1400) equals the number of relations checked
HINT: You have at least 1400 relations. Consider increasing the
configuration parameter "max_fsm_relations".
VACUUM

But there nearly only 300 tables in that db. Is the free space map is per
DB or for all DB. Can i know the reason of this problem?

-Arvind S

*

"Many of lifes failure are people who did not realize how close they were to
success when they gave up."
-Thomas Edison*