I found the following quote on the wikipedia page for the ZFS file system (
http://en.wikipedia.org/wiki/ZFS)

Quoting Jeff Bonwick (http://en.wikipedia.org/wiki/Jeff_Bonwick)

Although we'd all like Moore's
Law<http://en.wikipedia.org/wiki/Moore%27s_Law>to continue forever,
quantum
mechanics <http://en.wikipedia.org/wiki/Quantum_mechanics> imposes some
fundamental limits on the computation rate and information capacity of any
physical device. In particular, it has been shown that 1
kilogram<http://en.wikipedia.org/wiki/Kilogram>of matter confined to 1
litre <http://en.wikipedia.org/wiki/Litre> of space can perform at
most 1051operations per second on at most 10
31 bits of information.[10] <http://en.wikipedia.org/wiki/ZFS#cite_note-9> 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. To operate at the
1031bits/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<http://en.wikipedia.org/wiki/Joule>.
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<http://en.wikipedia.org/wiki/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.[11]<http://en.wikipedia.org/wiki/ZFS#cite_note-10>


Nothing like imposing some hard limits on a system :-)

Andy

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups 
"NLUG" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at 
http://groups.google.com/group/nlug-talk?hl=en
-~----------~----~----~----~------~----~------~--~---

Reply via email to