I noticed a bunch of almost new instances shoot up by several thousand users yesterday as well. My guess is people are using bots to create thousands of accounts, and this is gonna result in all manner of issues soon enough.
And its gone, I get a 404 when trying the load the website, good riddance.
404: FetchError: invalid json response body at http://lemmy:8536/api/v3/site? reason: Unexpected token 'T', "Timeout oc"... is not valid JSON
That wouldn't explain where the 6112 users suddenly came from.
I noticed this as well. Within just a few hours a whole bunch of newer instances have suddenly shot up by several thousand users each. My guess is that people are using bots to take advantage of the sign-up bugs and are creating thousands of bot account to use in various annoying and nefarious ways in the near future.
Maybe. Instances full of lurkers ... it makes sense.
You can see the communities that users of that instance have subscribed to from the instance's main page: communities -> All.
In the case of parapheum, there's a few but not that many ... I'd expect more given a user base of ~7k.
If you go to fedidb (https://fedidb.org/software/lemmy ) they list the MAU (monthly active users) for each instance. Instances like parapheum only have like 1 or a few MAU. As I understand, to be an "active" user, one must post at least once. I presume this includes comments as well as full posts. If so, there should really be more than 1 MAU for ~7k users. So it's hard to tell.
I've checked the admins of a couple of these instances, and they seem to be real and have had interactions ... so maybe we should ask some of them what's up.
If you visit the frontpage of that instance, there are 6k registered users and 3 users online (0.1% active). Lemmy.ml is the oldest instance with the most abandoned accounts, and a few weeks ago was like 30k registered and 1k online (~3% active, or 30x the parapheum instance). Other new instances like Lemmy.world have 30k registered and 3k+ active (~10%, or a further ~3x in active percentage over lemmy.ml due to fewer old/abandoned accounts).
I have no inside info, but that distribution of active vs registered users doesn't seem organic. And other posts yesterday were pointing out a rapid rise in registered Lemmy users detected by observer sites without a corresponding rise in active users. Something seeme wrong here, whether it's nefarious I dunno. Maybe this admin created a bunch of accounts to do performance testing before publicly launching their instance and just left them there, which would be a respectable thing to do.