MariaDB Inserts are getting slower and slower (7x tables, ~ 2.8M and 200MB)
I feel embarrassed :/, turned out that there were missing important indexes :(

Run for around night with ~ 1800k/s inserts (for endpoint, from mysql there would be probably 6 inserts + 4 reads for each endpoint insert, so ~ 10k/s of inserts + 8k/s reads).

In total over 150M records were created, > 30GB of data, no slow downs, still going fast.

RAM usage ~ 100% that was set for MySQL (32GB).

Really happy with it now :)

Of course replication will be another though decision, but for anyone else.

Make sure that proper indexes are in place, performance here degrade quickly.