For many this may be quite an obvious thing, but it went unnoticed in our app for a year so I still think it is worth sharing. We had over 70.000 entries in System.ScheduledEventInformation. As it is a system table, I asked support what to do about it. The answer was quite simple: there is no problem in deleting old data from it. Even if you did not create any scheduled events, the table might still fill up because other modules use them. Like CommunityCommons and the iCalendar module. This may go unnoticed because the System page that displays them no longer exists in many templates. Just for the fun of it I created a model share, it uses a constant for the retention value. https://modelshare.mendix.com/models/e933f85b-8a26-46c5-b178-602a96a22464/scheduled-event-cleanup Model share link
Note, if you have a lot of records in your table a 'retrieve all' might cause problems, and a retrieve/delete in batches is the preferred way to clean up your table
I woke up to the realization that I need to purge this entity when it grew to 6M records. I tried this module (https://marketplace.mendix.com/link/component/117292). It took me 20 mins to simply to extract the latest 10K records, and they never got removed. Mendix grew my database size till it simply hit the limit. Maybe, Mendix was creating some back up data, or it was growth of a roll back segment…
Anyways, how can I start purging System.ScheduledEventInformation entity with 6M records in it and growing at 10K records per day?
Mendix: “We'll be implementing an automatic cleanup mechanism in the coming months” (see idea 1714)