Would 4M qps be enough? :-) SQLite can achieve this with some help: https://blog.expensify.com/2018/01/08/scaling-sqlite-to-4m-qps-on-a-single-server/ https://

Would 4M qps be enough? :-) SQLite can achieve this with some help: https://blog.expensify.com/2018/01/08/scaling-sqlite-to-4m-qps-on-a-single-server/ https://blog.expensify.com/2018/01/08/scaling-sqlite-to-4m-q... More seriously, I suspect that plain SQLite by itself, running in process in the main service, writing to a ':memory:' database for ultimate speed or perhaps to a local file with WAL mode for slightly more durability, could achieve pretty nice efficiency and work as the main transaction manager database.