If "SLAP_DBFLAG_CLEAN" is not set for a backend database, the initialization process of the syncprov overlay reads all entries in the backend database.
As a result, slapd startup time will increase on the back-wt database with a large number of entries.
So, back-wt should be set "SLAP_DBFLAG_CLEAN" in back-wt/init.c.
If "SLAP_DBFLAG_CLEAN" is not set for a backend database, the initialization process of the syncprov overlay reads all entries in the backend database.
As a result, slapd startup time will increase on the back-wt database with a large number of entries.
So, back-wt should be set "SLAP_DBFLAG_CLEAN" in back-wt/init.c.