Wednesday, September 12, 2007

Quick ZFS nerd humor

As I was reading a little more about ZFS for a project today, I came across this Wikipedia entry, which I thought was humorous in a nerdy sort of way - and I figured you readers would enjoy if you haven't seen it yet. We've all heard the term "boil the ocean" but this takes it to a whole new level: (quoted directly from Wikipedia here...)

Project leader Bonwick said, "Populating 128-bit file systems would exceed the quantum limits of earth-based storage. You couldn't fill a 128-bit storage pool without boiling the oceans."[1] Later he clarified:

Although we'd all like Moore's Law to continue forever, quantum mechanicskilogram of matter confined to 1 liter of space can perform at most 1051 operations per second on at most 1031 bits of information [see Seth Lloyd, "Ultimate physical limits to computation." Nature 406, 1047-1054 (2000)]. A fully populated 128-bit storage pool would contain 2128 blocks = 2137 bytes = 2140 bits; therefore the minimum mass required to hold the bits would be (2140 bits) / (1031 bits/kg) = 136 billion kg. imposes some fundamental limits on the computation rate and information capacity of any physical device. In particular, it has been shown that 1

To operate at the 1031 bits/kg limit, however, the entire mass of the computer must be in the form of pure energy. By E=mc², the rest energy of 136 billion kg is 1.2x1028 J. The mass of the oceans is about 1.4x1021 kg. It takes about 4,000 J to raise the temperature of 1 kg of water by 1 degree Celsius, and thus about 400,000 J to heat 1 kg of water from freezing to boiling. The latent heat of vaporization adds another 2 million J/kg. Thus the energy required to boil the oceans is about 2.4x106 J/kg * 1.4x1021 kg = 3.4x1027 J. Thus, fully populating a 128-bit storage pool would, literally, require more energy than boiling the oceans.[5]

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