LIBRANET.de is a Friendica node. This is its public channel for maintenance announcements and general informations about the service. Also applies to venera.socialπ misskey.de and hub.libranet.de.
I don't know what exactly the database is doing since 24 hours. But it is remarkably heavy. The network traffic is on a normal level. So it must be some clean up process. I see a lot (up to 11000 qps) of 'update' and 'delete' queries. π€