ParadeDB uses Postgres’ settings, which can be found in the postgresql.conf file. To find your postgresql.conf file, use SHOW. 
SHOW config_file;
These settings can be changed in several ways:
  1. By editing the postgresql.conf file and restarting Postgres. This makes the setting permanent for all sessions.
  2. By running SET. This temporarily changes the setting for the current session. Note that Postgres does not allow all postgresql.conf settings to be changed with SET.
SET maintenance_work_mem = '8GB'