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Proposed Disk Array With 99.999% Availablity For 4 Years, Sans Maintenance
Thorfinn.au writes with this paper from four researchers (Jehan-François Pâris, Ahmed Amer, Darrell D. E. Long, and Thomas Schwarz, S. J.), with an interesting approach to long-term, fault-tolerant storage: As the prices of magnetic storage continue to decrease, the cost of replacing failed disks becomes increasingly dominated by the cost of the service call itself. We propose to eliminate these calls by building disk arrays that contain enough spare disks to operate without any human intervention during their whole lifetime. To evaluate the feasibility of this approach, we have simulated the behaviour of two-dimensional disk arrays with N parity disks and N(N – 1)/2 data disks under realistic failure and repair assumptions. Our conclusion is that having N(N + 1)/2 spare disks is more than enough to achieve a 99.999 percent probability of not losing data over four years. We observe that the same objectives cannot be reached with RAID level 6 organizations and would require RAID stripes that could tolerate triple disk failures.
Many high end equipment does have fairly large capacitors to allow enough power off time to do a clean power off.
I remember back in the 1990's some PC Centric folks were looking in a Sun Workstation they were surprised about all the large capacitors that were on the motherboard. In short it gives the system enough time finish its final calculation before the power goes out.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
In your fantasy there is a difference besides a hideously higher price and a somewhat longer warranty period. In real life, commodity SATA is much more cost effective. Everybody who is serious reognizes this (Google, Backblaze, Amazon).
Sloppy calculation tip: 24*365 = 10000.
If you're Sloppy enough to accept that premise, then at 10 cents/KWHr, a Watt costs a dollar per year. It makes your $28 turns into $32, but hey, close enough. When I'm shopping, I can add up lifetime energy costs really fast, without actually being smart. Nobody ever catches on!
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