Technology

And you can get 128-bit data to the CPU, so those things can be fast if we need them to be.

There's plenty of instructions for processing integers and fp numbers from 8 bits to 512 bits with a single instruction and register. There's been a lot of work in packed math instructions for neural network inference.

What about this is not my point?

In other words like GPUs. GPUs suck ass at complex calculations. They however, work great for a large number of easy calculations, which is what is needed for graphics processing.

Presumably you’d have a QPU in your regular computer, like with other accelerators for graphics etc, or possibly a tiny one for cryptography integrated in the CPU

Being pedantic, but...

The amd64 ISA doesn't have native 256-bit integer operations, let alone 512-bit. Those numbers you mention are for SIMD instructions, which is just 8x 32-bit integer operations running at the same time.

Intel PAE if the answer, but it still came with other issues, so 64 was still the better answer.

Also the entire article comes down to simple math.

Bits is the number of digits.

So like a 4 digit number maxes out at 9999 but an 8 digit number maxes out at 99 999 999

So when you double the number of digits, the max size available is exponential. 10^4 bigger in this case. It just sounds small because you’re showing that the exponent doubles.

10^4 is WAY smaller than 10^8

It was actually 3gb because operating systems have to reserve parts of the memory address space for other things. It's more difficult for all 32bit operating systems to address above 4gb just most implemented additional complexity much earlier because Linux runs on large servers and stuff. Windows actually had a way to switch over to support it in some versions too. Probably the NT kernels that where also running on servers.

A quick skim of the Wikipedia seems like a good starting point for understanding the old problem.

https://en.m.wikipedia.org/wiki/Wikipedia

Only slightly related, but here's the compiler flag to disable an arbitrary 2GB limit on x86 programs.

Finding the reason for its existence from a credible source isn't as easy, however. If you're fine with an explanation from StackOverflow, you can infer that it's there because some programs treat pointers as signed integers and die horribly when anything above 7FFFFFFF gets returned by the allocator.

https://en.wikipedia.org/wiki/Physical_Address_Extension

We are.

Addressing-wise, no we don't have consumer level 128bit CPUs and probably won't ever need them.

Instructions though, SSE had some 128bit ops (OR/XOR, MOVE) and AVX is 128bit vector math. AVX2 is 256bit vector math, AVX512 is- you guessed it 512bit vector math. AltiVec on PPC had 128bit vectors 20 years ago.

There's no benefit.