PostgreSQL includes the VACUUM statement, which reclaims waste storage using dead tuples inside the database. This is because when we delete tuples, they are not physically removed from their table until a vacuum is called. So, on frequently updated tables, we need to perform VACUUM periodically.
The PostgreSQL autovacuum launcher is an optional daemon. By default, it is enabled inside the PostgreSQL configuration using the autovacuum = on parameter. Therefore, unless you turn it off, the autovacuum launcher will wake up every autovacuum_naptime seconds.
Whenever the autovacuum occurs, by default, every 1 minute, it invokes multiple processes. The number of concurrent vacuum processes is defined by the autovacuum_worker parameter value inside the PostgreSQL configuration file. The vacuum work does not lock on any tables, hence it does not interrupt other database tasks.