Digital Packrats Rejoice: Disks just keep getting cheaper
I recently read “Where’s My Petabyte Disk Drive” and it reminded me of a talk that I gave with Ben Collins-Sussman and Jon Trowbridge back in 2007. Ben and I spoke about version control and Jon spoke about the rapidly declining costs of disk drives (and I took the liberty of adding the 2016 quote to Jon’s list):
The Cost of 1 GB of storage:
1986: $100,000.00
1990: $10,000.00
1994: $1,000.00
1997: $100.00
2000: $10.00
2004: $1.00
2007: $0.30
2016: $0.03
That’s a pretty amazing cost drop over 30 years. We’ve gotten to a point where disk storage is practically free, which is great for me because I don’t like to delete anything!
Even better: Jon made some 2007 guesses on where disk storage would be in 2016 (hey! that’s today!). Here’s one of his slides from 2007:
Good guesses based on growth of drive storage, and Jon was only off by about an order of magnitude (and, of course, we both got a laugh out of “video iPods.”).
But, as you can see from Brian’s graph in “Where’s My Petabyte Disk Drive?” drive density has slowed down considerably since about 2003:
So disk storage density and size growth is slowing down, but still increasing, and costs are still dropping for disk drives. But most consumer devices these days (laptops, and definitely not tablets or phones) don’t even contain a spinning disk. Solid state drives (or SSDs) are taking the place of hard drives for non-RAM storage.
In 2007, we didn’t even consider the fact that SSDs would become a thing. And as of today, the cost per gigabyte for a solid state drive?
About $0.25. Here’s the current trend for SSD cost in dollars per GB (most prices from here, converted to 2016 dollars):
1976: $165,350,000.00 (!)
1978: $33,856,000.00
1982: $17,591,000.00
1988: $640,500.00
1992: $231,551.00
2003: $4,086.00
2006: $26.26
2013: $0.68
2014: $0.55
2015: $0.30
2016: $0.25
Unlike hard disk prices, SSD prices seem to be dropping much more slowly nowadays as we approach physical limits. When do you suppose that they will hit $0.03? My reckless extrapolation is sometime in 2023.
Thanks to Karen Wickre, Tim Bray, and Jas Strong for reading through this and providing suggestions.
