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# 2^64 bytes is enough for any human

## 2^64 bytes is enough for any human

Posted Apr 15, 2004 13:53 UTC (Thu) by zooko (subscriber, #2589)
Parent article: The Grumpy Editor goes 64-bit

Do you think that we will someday need more memory than can be addressed with 64 bits?

2^64 is 18,446,744,073,709,551,616. That's 17,179,869,184 gigabytes.

Suppose you had some kind of memory storage device which could store 1 gigabyte in a 1 millimeter by 1 millimeter square. Then your whole system would occupy a field 130 meters by 130 meters. Or you could go 3-D -- suppose you have a 1 GB device 1 millimeter by 1 millimeter by 1 millimeter. Then you would need a volume 2.5 meters by 2.5 meters by 2.5 meters to hold enough of these devices to store 2^64 bytes.

And what would you store in there? Let me put it another way -- what's your max bandwidth? How many bytes of data can you meaningfully produce or consume in a second? Let's say that you will someday produce and/or consume 1 GB per second, and you want to store all of this stuff for possible later use. Then this device that you have can store enough of this data for 544 year's worth of uninterrupted, non-repeating production/consumption.

Maybe corporations, AIs, or neo-humans will have use for such amounts of memory, but I don't think that humans will!

2^64 bytes is enough for any human

Posted Apr 15, 2004 17:59 UTC (Thu) by fjf33 (subscriber, #5768) [Link]

Back when people were storing bits in induction coils nobody though that we would need 1 MB of ram and the future computeres were the size of planets. What makes you think that the rate of growth would slow any? It sounds like a couple of Mols of memory cells would do the trick pretty well in a very small space. It just will be different. It may also be that future MMOGs will be simulating things so close to reality that 2^64 would be reasonable.

2^64 bytes is enough for any human

Posted Apr 16, 2004 21:31 UTC (Fri) by giraffedata (subscriber, #1954) [Link]

Back when people were storing bits in induction coils nobody thought...

I'm always suspicious of these statements. Throughout history, people have been smart and imaginative.

Though I was not talking to people about memory sizes in those days, I'm sure anyone who thought about it seriously realized we would need 1MB of memory in a computer.

They quite possibly didn't think we'd ever be able to get it, but that's a whole different discussion.

I guess we could put it another way: Nobody thought in the future we would need 20 bit addresses. (Because we'd never be able to get 1MB of memory behind a single CPU).

2^64 bytes is enough for any human

Posted Apr 20, 2004 16:47 UTC (Tue) by zooko (subscriber, #2589) [Link]

At some point, the "we'll always need more" belief has to be wrong. For example: do you think we'll need more than 2^128 memory? I don't. How many atoms of matter are there in the universe?

2^64 bytes is enough for any human

Posted Apr 23, 2004 0:03 UTC (Fri) by chant (subscriber, #20286) [Link]

First, imagine some sort of 3-d movie.
Then, an interactive 3-d movie.
Then consider a large-scale 3-d movie; i.e. modelling what happens to each of those atoms in the universe over time.
Or, perhaps, modelling the little tiny components (and sub-components ad nauseum) of even one of those atoms. The possibilities are endless.... and perhaps, storing the 'feel' & phyiscs reacions of physical textures, the bonds between each of those atoms, etc.

Or....on another order of magnitude altogether, the binaries for Windows U[niverse]E.

:)

2^64 bytes is enough for any human

Posted Apr 27, 2004 21:01 UTC (Tue) by slamb (guest, #1070) [Link]

The point is not whether or not it would be useful to have an accurate model of the universe, but that it is impossible. Clearly you can't do better than (or even as well as) harnessing the largest set of good quantum numbers of every particle in the universe. (Your computer has to be in the universe!) So by examining the number of particles in the universe, you can come up with a number that is larger than the maximum possible storage space of a computer. Take the base-2 log and you've got an inexhaustible address space.

I've seen discussions of this number before, but I don't remember the result. But I seem to recall it being less than 2^128; thus, a 128-bit address space is good enough for anyone. Really.

There are other arguments based on thermodynamics limiting the complexity of a computer. Google for discussions of thermodynamics and reversible vs. irreversible computers and you'll see what I mean.

2^64 bytes is enough for any human

Posted Apr 15, 2004 18:26 UTC (Thu) by tjc (subscriber, #137) [Link]

Suppose you had some kind of memory storage device which could store 1 gigabyte in a 1 millimeter by 1 millimeter square. Then your whole system would occupy a field 130 meters by 130 meters. Or you could go 3-D -- suppose you have a 1 GB device 1 millimeter by 1 millimeter by 1 millimeter.

And just think how long it would take for the POST to count all that! :-) You'd need a pretty fast CPU too..

2^64 bytes is enough for any human

Posted Apr 16, 2004 3:29 UTC (Fri) by wolfrider (guest, #3105) [Link]

--To blazes with the POST; you'd basically have to check that much memory on-the-fly (before malloc returns) and/or in the background.

2^64 bytes is enough for any human

Posted Apr 16, 2004 21:24 UTC (Fri) by giraffedata (subscriber, #1954) [Link]

Do you think that we will someday need more memory than can be addressed with 64 bits?

I do, but the question you've answered is really, will we someday need more than 2^64 bytes of memory in a computer like the ones we have today?

You've made an excellent argument that the answer to that question is no.

On the other hand, I'm sure some day computers will be structured differently, and we will most likely be addressing memory larger than what fits on a motherboard, or even in one building. There is definitely more than 2^64 bytes of information to be stored in the world. We'll struggle for a while with all the usual stopgaps -- paging, multilevel addressing, and such. But eventually we'll break down and get more than 64 bits of address space and go through a transition much like the 32/64 one.

2^64 bytes is enough for any human

Posted Jan 18, 2011 10:24 UTC (Tue) by stealthpaladin (guest, #72424) [Link]

now that years have gone by and whatnot, i think this is even a bit more interesting.

Some time around 2009 Google CEO estimates 500 million terabytes of data attributed to the internet.

So by now, we could probably use a 2^64 computer to hold 2.x backups of the internet =P Which could have it's uses =P

as goes 2^128 and this idea
"Clearly you can't do better than (or even as well as) harnessing the largest set of good quantum numbers of every particle in the universe. (Your computer has to be in the universe!) "

Well there are ways to take a few values (say 8 for example) and based on these achieve further resolution than 8 (say 256 for example =P) Really there are many techniques which provide more resolution for processing and storage than their components, so I think identifying the whole universe may not be so impossible really.

I also think of the whole,... leaf in a pond thing. There's an idea that if you can *fully* define and understand one particle on the leaf then you can access the info of the entire pond. Perhaps with 2^128 we could define one proton so well that everything else is just implied lol.

2^64 bytes is enough for any human

Posted Jan 18, 2011 10:28 UTC (Tue) by stealthpaladin (guest, #72424) [Link]

5 million* i mean lol