18-Mar-2013 14:25, bearophile пишет:
Walter Bright:
That's just not an issue when you have 64 bits of address space. You
can still have 4 billion stacks of 4 billion bytes each.
At this point I suggest you to study exactly why Rust developers have
decided to use a segmented stack. It seems to work well for them.
Walter's position is crystal clear.
IMHO virtual memory was designed among other things to avoid piecing
together segmented memory blocks by hand. Memory manager (OS) will od
the whole dirty work for you and even hardware assists the process
resulting in decent speed and complete transparency of operation. Why
destroy this marvelous creation of hardware and OS developers?
The whole segmented stack thing smells a lot like good ol' 16-bit days
and is a step backwards unless you assume that:
a) There is no virtual memory i.e. no MMU. Well, some MCU units are
still like this but the trend goes towards having MMU even on tiny chips.
b) Virtual ram / physical ram relation is close to 1 or even worse, like
in 32-bit OS running on 8G desktops. As for virtual memory to be truly
exploitable address space better be many times the total ram, the more
the better.
Both cases do not seem likely to be related to the future technology
like at all.
Bye,
bearophile
--
Dmitry Olshansky
