Post by Chris Mellor (thank you) over at El Reg
4.95 PB in a standard data centre rack
For maximum big data density, you basically need a rack full of disk drives and little else, and DataDirect has moved in that direction by stuffing up to 840 disks into a standard rack cabinet.
The idea is that HPC and big data environments need as much capacity in a storage rack as they can get. DDN reckons it offers up to 40 per cent more capacity than its competitors in this area.
Read on here