Robert Haas <robertmhaas@gmail.com> writes:
> I've often thought that 64-bit machines are so capable that there's no
> reason to go any higher. But lately I've started to wonder. There
> are already machines out there with >2^40 bytes of physical memory,
> and the number just keeps creeping up. When you reserve a couple of
> bits to indicate user or kernel space, and then consider that virtual
> address space can be many times larger than physical memory, it starts
> not to seem like that much.
> But I'm not that excited about the amount of additional memory we'll
> eat when somebody decides to make a pointer 16 bytes. Ugh.
Once you really need that, you're not going to care about doubling
the size of pointers. At worst, you're giving up 1 bit of address
space to gain 64 more.
(Still, I rather doubt it'll happen in my lifetime.)
regards, tom lane