Currently the database consistency check runs as a separate process prior Ambari process. The database consistency checker load various modules needed for performing the validations. (e.g. load stack definitions to be able to compare service configs from stack with configs from db).
Once database consistency checker completed Ambari server is started. Ambari server beside others loads the same modules as database consistency checker.
This double initialisation adds time to the ambari server startup time which could be reduced if the database consistency check is moved into the ambari server process.
Moreover the database consistency check may check at the beginning if the database is empty and perform the checks only if there is data in the database.