I experienced this on my own little instance as well, although they managed to create 69000+ users before I noticed that something weird might be going on and I got a message from a helpful soul indicating the same thing.
I was pointed to a writeup by lemmy.ninja @ https://lemmy.ninja/post/30492 on how they experienced this and proceeded to clean everything up, and adapted this to my own instance. Only thing to mention of note was that I disabled triggers while doing the cleanup. The DELETE statements on person table was excruciatingly slow to the point where I estimated that time to completion approached 48 hours.
I experienced this on my own little instance as well, although they managed to create 69000+ users before I noticed that something weird might be going on and I got a message from a helpful soul indicating the same thing.
I was pointed to a writeup by lemmy.ninja @ https://lemmy.ninja/post/30492 on how they experienced this and proceeded to clean everything up, and adapted this to my own instance. Only thing to mention of note was that I disabled triggers while doing the cleanup. The DELETE statements on person table was excruciatingly slow to the point where I estimated that time to completion approached 48 hours.