It's been a while since I've checked this but a few years ago we tried to limit test kine on a large-ish cluster and it performed pretty poorly. It's fine for small clusters but the way they have to implement the watch semantics makes it perform poorly (at least this was the case a few years ago).
Agreed. The subscriptions really is a huge huge part of the magic, and it's a weakpoint of Kine. Thanks for chiming in.
Ideally, i'd love to see a database specific offering. Use postgres async replication (ideally somehow sharded so there's not a single consumer node) to some fan out system that's doing all the watching.
But etcd mostly does the job, seems unlikely to be going anywhere. It's be cool though.