Comment by creiht

It is probably worth noting that most of the listed storage systems (including S3) are designed to scale not only in hard drives, but horizontally across many servers in a distributed system. They really are not optimized for a single storage node use case. There are also other things to consider that can limit performance, like what does the storage back plane look like for those 80 HDDs, and how much throughput can you effectively push through that. Then there is the network connectivity that will also be a limiting factor.