in my case using the in-memory ETS has been the best decision, it lets me read&write the peer's data concurrently each on its own process so contention and latency are minimal. the only sequential part is when a new swarm is initially created but that doesn't happen a lot so its fine. there's sadly no native support for taking random rows directly from the tables, so for now i grab the whole swarm and then take a random subset (https://github.com/Dahrkael/ExTracker/blob/master/lib/ex_tra...)

I don't remember if there's a way to see how many slots an ets table has, but if you're ok with imperfect distribution, you could maybe pick a slot at random and use ets:slot/2 to get all the items in that slot, then select from those.

You might be able to get the slot count from eta:table_info(Table, stats), although that's not intended for production use, so the format may change without notice.