The zmaudit daemon exists to check that the saved information in the database and on the filesystem match and are consistent with each other. If an error occurs or if you are using 'fast deletes' it may be that database records are deleted but files remain. In this case, and similar, zmaudit will remove redundant information to synchronise the two data stores. The default check interval of 900 seconds (15 minutes) is fine for most systems however if you have a very large number of events the process of scanning the database and filesystem may take a long time and impact performance. In this case you may prefer to make this interval much larger to reduce the impact on your system. This option determines how often these checks are performed.