Comment by synsqlbythesea

In a few words: table data is stored on hundreds of MariaDB servers. Each table is user designed hash key columns(1->32) to manage automatic partitioning. Wide tables are split in chunks. 1 chunk = the hash key + columns = one MariaDB server. The data dictionary is stored on mirrored dedicated MariaDB servers. The engine in itself uses a massive fork policy. In my lab, the k1000 table is stored on 500 chunks. I used a small trick : where I say 1 MariaDB server you can use one database in a MariaDB server. So I have only 20 VmWare Linux servers with 25 database each containing 25 databases.