Hello,
It finally turns out that this file is used for other purposes than real logging.
The referint plugin currently works like that; When the delay update is set to be more than 0 a new thread is created executing referential integrity code every x seconds (set by delay update). When a delete or modrdn operation happens, the plugin will write that down to its logfile. So, every x seconds the plugin will check the logfile, see what happened and apply the changes. Finally, it deletes the file, thus clearing the state for the next time it reads from it.
After discussing this with William he suggested it's better to replace the file with a queue, since the file involves excess fsync / sync, and has all kinds of potential state/race issues. Using a queue will be much faster as well.
William went even further and suggested that we
could get rid of the async referint update completely. This probably
wouldn't happen soon though, since likely customers are using it. For now we could provide a warning such as "we recommend you set delay to 0".
Finally, the referint-logchanges attribute does absolutely nothing. It seems to be completely ignored by the plugin, so we could remove this as well.