Kinda comparing apples to oranges. AWS was using EBS and not local instance storage. So you’re easily looking at another order of magnitude latency when transmitting data over the network versus a local pcie bus. That’s gonna be a huge factor in what I assume is a heavy random seek load.

I wrote a longer comment already (https://news.ycombinator.com/item?id=47352526) but looking at the hot run performance and making big hand wavy guesses, the performance difference might not be as big as you'd expect.