How to effectively re-create and tune the Retro Changelog in RHDS / IPA ?

Issue

the retro changelog plugin in RHDS / IPA consists on a database where we log all the database updates taking place in the system. It's useful for monitoring purposes but it could be also useful for some clients application.

For instance, in IPA the retro changelog database is used by the Content Synchronization Plugin that implements RFC 4533 and it's used by DNS component to learn about changes in the DNS subtree.

As the number of updates could be high, particularly in IPA, we can see failures of this sort:

[01/Jun/2018:17:19:32.352173350 +0300] DSRetroclPlugin - delete_changerecord: could not delete change record 32144044 (rc: 32)
[01/Jun/2018:17:19:32.353563771 +0300] DSRetroclPlugin - delete_changerecord: could not delete change record 32144045 (rc: 32)
[01/Jun/2018:17:19:32.355249453 +0300] DSRetroclPlugin - delete_changerecord: could not delete change record 32144046 (rc: 32)
[01/Jun/2018:17:19:32.356567206 +0300] DSRetroclPlugin - delete_changerecord: could not delete change record 32144047 (rc: 32)

If we find them and they are just transient, we can ignore. If the messages repeat constantly, we will have to delete and re-create the retro changelog.