Re: 4GB memory and Intel Dual-Core system

[Fawad Lateef <fawadlateef@gmail.com>]

On 10/28/05, Joel Jaeggli <joelja@darkwing.uoregon.edu> wrote:
> On Fri, 28 Oct 2005, Fawad Lateef wrote:
>
> > Can you tell me the main differences between IA64 and x86_64 (Opteron)
>
> IA64 is itanium - there are a lot of differences but the principle one for
> your perspective is that you don't want to run x86 code on a itanium, it
> has an x86 instruction decoder but you wouldn't want to use it if you
> could avoid it.
>

OK

> > ? because in your one of the previous mail you said IA64 != EM64T and
>
> emt64 getts lumped with amd64 collectivly x86_64. fundamentaly intels
> implementation is compatible with amd's
>
> > its true, but I know is EM64T/AMD64 in 64-bit mode != IA32 but you
> > said that too EM64T is not really 64-bit, its a IA32 .. Can you give
>
> It is ia32 except with 40 bits of real memory and 48 bits of virtual
> memory and 64 bit registers.
>

And a difference of memory architecture is there tooo. x86_64 in
64-bit mode implements flat memory model but IA32 uses
segmentation/paging. As far as Linux Kernel is concern I know kernel
won't implements segmentation in IA32 so it memory management is
almost compatible with x86_64 except registers/real address /virtual
addresses ...

> one article that's use for getting a start on the instruction set is here:
>
> http://arstechnica.com/cpu/03q1/x86-64/x86-64-1.html
>

Thanks, nice link :)

>
> > me some link which just tells the difference between IA64 (Itanium)
> > and AMD64 (Opteron) ?
>
> you're not likely to care about ia64, so I think what your'e really
> interested in is ia32 vs x86_64 and intel vs amd in the context of x86_64
>

Nops, I am not interested in x86_64 context of intel and amd, I rather
wanted a comparison between the intel and amd server processors
architecture (Itanium and Opteron).

Any ways, Thanks


--
Fawad Lateef