After significant changes are made to a database schema, overflow can occur on internal system tables (often referred to as system catalogs). For optimum performance, these internal tables should be re-balanced after the schema is created.

Sysmod is the command-line utility that re-balances the system catalogs to ensure that they are optimized for rapid access. It should be run after significant changes to the database schema, such as creating the schema for the first time or running optimizedb for the first time. It can be executed as follows: