> like what kind of hardware would be optimal for S3's workload
> how to support strong consistency like S3 does without impacting system performance
I think most of these questions are first and most importantly _hardware_, _money_ and _physics_ questions.
I have no expertise in this matter, but I think this would be a good proxy answer: you make a system _seem_ to have unlimited throughput by interconnecting _a lot_ of the fastest available storage solutions with the fastest available network cards, putting it as close as possible to where your users are going to be. All of this is extremely expensive so you would need to have deep pockets, as amazon has, to make it possible (or a lot of investment).
I suspect with the right hardware and physical deployment locations you could fine tune Ceph or MinIO or whatnot to similar performance as S3. S3 is an object storage so the distributed system aspects of its implementation should definitely be a lot easier than, say, distributed SQL (not saying either is an "easy" thing to accomplish).
If you are interested in which hardware to use for a SAN, I found these benchmarks that may be exactly what you are looking for :-) [1]
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