Q:

Is Autovacuum global setting applied to all tables? 

I have autovacuum globally enabled, sql query:
select * from pg_settings where category like 'Autovacuum'

shows that autovacuum setting is "on". 
Does that mean all tables in the database will be subjected to autovacuum periodically, or I need to additionally set autovacuum to "on" individually for every table in order to autovacuum it? 

A:

Yes, that means it's globally enabled.  
You don't need to turn on manually for each table.