That is why I asked, I am only aware of the use of IOPS in connection with disk I/O and it seems a rather unusual measure for a database where caches hopefully avoid hitting the disk too often, at least for reads. And writing 8 MiB/s assuming 4k clusters seems not really noteworthy especially given three fold redundancy. On the other hand reading 700 MiB/s per second which would also not be affected by the redundancy seems a comparatively big number especially because caches should limit the disk traffic to a small fraction.

Queries here are measured from the application side. And in our case, those are simple key-value operations such as get(key), update(key, value), write(key, value) and delete(key). Aerospike is known to optimize those into fewer block operation as it can.

This is mostly marketing. You can scale to infinity only if you're app is architected in a very particular way and you're properly using the underlying primitives (be prepared to shard, cache, and queue everything at some point; try to put thought into where your demarcation points will be, it will make future decoupling less painful). Even Aurora Postgresql and Mysql only scale so far.

One click it is not.