At regular intervals, the Directory Server writes operations logged in the transaction log to the database index files and logs a checkpoint entry in the database transaction log. By indicating which changes have already been written to the database indexes, checkpoint entries indicate where to begin recovery from the transaction log, thus speeding up the recovery process.

By default, the Directory Server is set up to send a checkpoint entry to the database transaction log every 60 seconds. Increasing the checkpoint interval may increase the performance of directory write operations. However, increasing the checkpoint interval may also increase the amount of time required to recover directory databases after a disorderly shutdown and require more disk space due to large database transaction log files. Therefore, only modify this attribute if you are familiar with database optimization and can fully assess the effect of the change.

To modify the checkpoint interval while the server is running, use the ldapmodify command-line utility to add the nsslapd-db-checkpoint-interval attribute to the cn=config,cn=ldbm database,cn=plugins,cn=config entry.

# ldapmodify -D "cn=Directory Manager" -W -p 389 -h server.example.com -x

dn: cn=config,cn=ldbm database,cn=plugins,cn=config
changetype: modify
add: nsslapd-db-checkpoint-interval
nsslapd-db-checkpoint-interval: 120

For more information on the syntax of the nsslapd-db-checkpoint-interval attribute, see the Red Hat Directory Server Configuration, Command, and File Reference.