Postgres fill factor
Looks like we can get some performance wins by reducing random IOPS if we change the fillfactor on tables that will get UPDATEs. Basically, a fillfactor of 90 means that the table is only filled up 90% with INSERTs and leaves a 10% unused gap for any modifications to the data so operations can stay sequential and changes don't spillover into new database files.
This parameter cannot be set for TOAST tables