4 Feb
2008
4 Feb
'08
5:06 a.m.
On Feb 4, 2008 2:36 AM, Erik de Castro Lopo <mle+la(a)mega-nerd.com> wrote:
david wrote:
Right. I presumed that he was comparing a 32 to a 64 bit OS on the
same (64 bit) hardware, in which case I would not expect a difference;
it's just as fast to load a 32 bit pointer as a 64 bit one. Unless
the compiler is smart enough to fetch two 32 bit words at once
whenever possible ;-)
Lee
Just curious, but I've heard that 64-bit OSes
are slower than 32-bit
ones. That seems odd to me. Any truth to it?
Swings and roundabouts.
On architectures like Sparc where the 32 and 64 bit CPUs have the same
number of registers, the 64 bit OS is likely to be a little slower
on operatrions like traversing linked lists because each pointer is
twice as big on 64 bit and hence each retrieval of a pointer requires
twice as much memory bandwidth as the 32 bit OS.