[GRLUG] 64-bit Linux

[Michael Mol]

On Fri, May 9, 2008 at 1:56 PM, Adam Tauno Williams
<adamtaunowilliams at gmail.com> wrote:
>> So I've got a brand-spankin-new laptop that I'd like to run Linux on.
>> Thing is, this is my first box with a 64-bit processor.  I don't yet
>> know if I want to run Ubuntu or Gentoo, but one problem remains: Do I
>> run 32-bit or 64-bit?
>
> 32;  it is easier, less fuss, and 64-bit on a laptop is entirely
> pointless.  64bit is not necessarily any faster and is even slower in
> some circumstances.  Use 64bit if you have oodles of RAM and run have
> processes that are enormous - both of which are unlikely on a laptop
> unless you are editing HD video.

Any x86-64 processor should have Intel's Paged Address Extensions,
giving 32-bit operating systems access to up to (IIRC) 64GB of RAM.  I
know it's possible on Linux, at the very least. See the "64GB high
memory" option if you configure and compile your own kernel.

I like x86-64 primarily because of the 8 GPRs that the compiler can
optimize for, instead of 4 GPRs on IA32.  I've done enough performance
coding to recognize how useful it can be to have that many more places
to store values and pointers, and avoid needing to call out to cache.

-- 
:wq