Migrating Facebook to MySQL 8.0
> First, we could not upgrade servers in place and needed to use logical dump and restore to build a new server. However, for very large mysqld instances, this can take many days on a live production server and this fragile process will likely be interrupted before it can complete.This part is quite interesting. I'd think it will take maybe a day to dump/restore a database with a single 10TB table with no parallelism, at a speed of about 120MB/s. How big is these mysqld instances such that the process will take many days?