You can trivially scale fdb to tens of millions of tx/sec for write-heavy workloads without a hardcore cluster for transactions of reasonable complexity (though with careful design on my part and the part of others for collisions to be unlikely).

MTTR on failure is seconds. Really, there's no system I've used that is as robust and performant as fdb and I include s3 in that list - s3, for example, _routinely_ has operations with orders of magnitude latency variance and huge, correlated spikes.

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