As always, I'm grateful to the Library of Congress for inviting me. I was asked to give a brief report of what happened at the DARPA workshop on "The Future of Storage" that took place at Columbia last May. There has yet to be a public report on the proceedings, so I can't be specific about who (other than me) said what.
Three broad areas were discussed. First, I and others looked at the prospects for bulk storage over the medium term. How long is the medium term? Hard disk has been shipping for 60 years. Flash as a storage medium is nearly 30 years old (Eli Harari filed the key enabling patent in 1988), and it has yet to make an impact on bulk storage. It is pretty safe to say that these two media will dominate the bulk storage market for the next 10-15 years.
|WD unit shipments|
The world's capacity to make bytes of flash would have to increase dramatically. There are two possible (synergistic) ways to do this; it could be the result of either or both of:
Flash vs HDD Capex
But even if the money is available, bringing new fabs into production takes time. In the medium term it is likely that the fabs will come on-line, and accelerate the displacement of hard disk, but this won't happen quickly.
- Increasing the bytes of storage on each wafer from existing fabs. Two technologies can do this; 3D flash is in volume production and quad-level cell (16 bits/cell) is in development. Although both are expensive to manufacture, the investment in doing so is a lot less than a whole new fab, and the impact is quicker.
Write endurance Source
- Reading the data may be cheap but is always going to be very slow, so the idea that "DNA can store all the world's data" is misleading. At best it could store all the world's backups; there needs to be another copy on some faster medium.
- The use of long-lived media whose writing cost is vastly greater than their reading cost is extremely difficult to justify. It is essentially a huge bet against technological progress.
- As we see with HAMR there is a very long way between lab demos of working storage media and market penetration. We are many years from working DNA storage media.
Thanks are due to Brian Berg and Tom Coughlin for input to this talk, which drew on the reporting of Chris Mellor at The Register, but these opinions are mine alone.