NEC Earth Simulator tape library

The oldest storage technology in this taxonomy and a reminder that "storage" meant something different before flash made random access to petabytes routine. System disk and user disk together held 640TB, small enough by later standards that most of the Earth Simulator's actual capacity, over 1.5PB, sat in a robotic tape library one step removed from the compute. That is the inverse of every modern system in this dataset, where tape if it exists at all is the cold archive tier beneath an all-flash burst buffer, not the majority of installed capacity.