> Of course, if somebody does an operating system that uses 128-bit addressing to address every byte in the world uniquely, and this takes over the world, it might be an impetus for 128-bitters :-)
I'd like to see such OS.
I'd like to see such OS.
Scary thought: how many bytes of RAM are there in the world? Probably more than 2^64. There are around 7 billion smartphones, and many have over 4GB of memory. That's over 2^64 right there.
I'd like to have 128-bit atomic operations. If you're doing lock-free programming, hardware compare and swap on a structure that contains two pointers is useful. Then you can update lists atomically. In a 64-bit pointer machine, that takes 128 bit atomics. So far, not much hardware offers that.
https://ebarnard.github.io/2019-06-03-rust-smaller-trait-imp...
https://github.com/rust-lang/rust/issues/32976
A little confusing but it looks like you can get to it.
[1] https://superuser.com/questions/187254/how-prevalent-are-old...
> It is the basic building block of modern electronics, and the most frequently manufactured device in history, with an estimated total of 13 sextillion (1.3×10^22) MOSFETs manufactured between 1960 and 2018
64 bits can address 1.8x10^19 bytes. Of course there is not a 1:1 correlation between mosfets ever made and bytes of ram usable today but it's curiously close to the 64-bit limit so you could say 64 bits is just enough to address every byte in the world.
I wonder how much magnetic storage would add to that?
A lot.
Just looking at hard drives, if you take an estimate of 250 million units made in 2020 and multiply by a conservative 4TB, you get 10^21 bytes for that single year.
* That's the threshold where you go from 128 to 256, not where you go from 64 to 128.
* If you're not going for the physically maximum overclock, the energy per bit is a lot less.
* That's for storing 512 byte blocks, so you'll run out of RAM bits 512 times sooner.
* Humans use about 10^20 joules of electricity per year.
* 10^20 joules at the cost in the link would be about 2^110 bytes, which is not all that far off.