Yes, considering the size of their operation, the length of time they’ve been running, and the variety of instance types they offer, it would be really surprisi

Yes, considering the size of their operation, the length of time they’ve been running, and the variety of instance types they offer, it would be really surprising to me if they didn’t have multiple generations. Also, they don’t offer {4,8}XL cluster {compute,GPU} instances in Oregon. If their infrastructure were homogeneous, there would be no reason not to. (Well, other than that those instance types are probably likely to have less latency-sensitive applications.) Clearly they run a pretty tight ship, but it doesn’t follow that something on the order of half a million machines all have exactly the same mount. And they could be 90% 1U-based (justifying the public statement) but, going by these figures, still have 45,000 non-1U servers.