Microsoft Developing a 128-bit Windows

This PCPro story says

“Microsoft is planning to make Windows 8 an 128-bit operating system, according to details leaked from the software giant’s Research department.”

Is this really a big deal? Are we going to need 128-bit operating systems?

I’m still using 32-bit distros and doing fine, though I know that 64-bit systems have a lot of practical value and are widely used. They handle larger files, more memory, and move more data, which speeds up demanding tasks like 3D video rendering, audio encoding, games, and databases. 64-bit systems can theoretically handle 16 exabytes of RAM and files up to 8 exabytes in size. In real life filesystem and hardware limitations determine what a 64-bit system can handle. Still, it’s far more than 32-bit, and far more than most users will ever need.

So what’s with this 128-bit future, is it really practical? Is anyone close to being limited by 64-bit? It seems that we expand our needs right along with our computing power, but 128-bit seems like a big leap. One commonly-cited estimate is that all the printed material in the world uses about five exabytes.

Sun Solaris already offers 128-bit computing— 2 to the 128th power bytes of storage, and 2 to the 64th power for everything else such as file systems, snapshots, directory entries, devices, and more. In comparison, one exabyte is 2 to the 60th power.

This Slashdot comment raises some interesting points:

“Most 64-bit processors provide 40 or 48 bits of address space; they ignore the other two or three bytes of the address (often they support a larger virtual address space than physical, but even then it’s usually less than 64-bit). I’ve yet to see a consumer-grade machine with more RAM than PAE (36-bit addressing) could address. That said, memory is not the only place where the number of bits is important. Hard drives are typically addressed by 512-byte blocks, so 32 bits gives you 2TB, which is a single disk these days. 64 bits gives you 8ZB, which is quite a lot, but it’s not a completely unreasonable amount; some people are going to find that constraining in the next few years, which is why ZFS uses 128 bits. It’s not that 128 bits are necessary, so much that 65 bits are and 128 is the most computationally-convenient size after 128. Making sure everything in the kernel supports 128-bit filesystem offsets is an important for long-term project.”

Of course my first reaction to the news that Windows is going 128-bit is “They couldn’t even get 64, 32, or 16-bit right.” But snarks aside, it seems this is coming, and as far as I know nobody is working on a 128-bit Linux. Does this really matter? Don’t ask me, I’m still on 32-bit :).


Microsoft mulling 128-bit versions of Windows 8, Windows 9

How Things are Measured.