Den-si-ty (n.): The quantity per unit volume, unit area, or unit length. (From Merriam Webster)
Generally speaking, no one wants to pay more than is minimally required in order to store their stuff. This is probably why so many American garages are filled with boxes and sports gear while the car sits out on the driveway. It’s less expensive to keep grandma’s knick-knacks and the kids’ hand-me-downs in the garage than it is to pay the folks at U-Store-It to hold it for next spring’s neighborhood yard sale.
When it comes to storing electronic bits, the same premise holds true. Administrators don’t want to pay more to store their data than is minimally necessary given various constraints around things like response times and availability. As a result, buying storage gear that provides great density at low cost becomes highly important. This is especially true given the length of time that bits have to be stored, which in some cases happens to be eternity.
So what’s the most dense, cost-effective storage for the long-haul? Tape. Given proven technology and vendor roadmaps, the effort to extend tape density and cost effectiveness continues unabated. In January, 2010, IBM and FUJIFILM demonstrated tape technology with a density 39 times greater than the best-in-class tape at that time.
Other notable tape density storylines include:
1) Hitachi and Maxell announced development of a 50 TB tape in May, 2010.
2) Oracle announced it was shipping a 5 TB tape drive in January, 2011.
3) The LTO consortium released a roadmap with a 12+ TB tape (LTO8) in April, 2010.
4) IBM announced shipment of a 4 TB tape drive in May, 2011.
Furthermore, the major tape drive vendors (IBM and Oracle) both specify that the cost per GB of disk is 5x to 10x more expensive than that of tape. As the density advances noted above continue, the cost per GB will continue to decline going forward. This means that the forecast for long-term, cost-effective storage on tape will continue to be attractive relative to that of disk. This is particularly true for those customers facing significant active archive requirements. Could this be the reason Why Tape Rolls On?
To learn more about Why Tape Rolls On, see part 3 of this series discussing the Speed of tape.