Which all system parameters to be considered for standard Vacuum process
The default settings will probably be fine.  

That will limit the IO write usage to about 4MB/sec, that is, 4kB/msec = (8KB * vacuum_cost_limit / vacuum_cost_page_dirty / autovacuum_vacuum_cost_delay)

And RAM usage to about 48 MB (autovacuum_max_workers * maintenance_work_mem)