Before you start writing code and making architecture decisions, you need to do some sanity testing. Can you even run 15,000 SQL inserts per second of the forma

Before you start writing code and making architecture decisions, you need to do some sanity testing. Can you even run 15,000 SQL inserts per second of the format you want on a single machine? If not, you may need to abandon using a database entirely. You can test this with a simple script and the results might invalidate your whole plan. Also, I'm betting you don't actually need to support this kind of load to do what you want to do. In particular you can probably batch up data, since you are going to have latency issues anyways. You need a specific target for the latency you need, and then do some measurement figuring out how much batching you can do. Why don't you explain your idea in more detail? The community can probably be more helpful then.