Re: EM64T server kernel architecture - ia32e or x86_64?

[Brian Long <brilong cisco com>]

On Fri, 2004-12-17 at 03:52, Arjan van de Ven wrote:
> On Fri, 2004-12-17 at 08:09 +0100, Jay Turner wrote:
> > On Fri, Dec 17, 2004 at 11:25:38AM +1100, Guy Waugh wrote:
> > > I guess this raises the question 'what is the difference between the 
> > > [non-SMP] ia32e kernel and the [SMP] x86_64 kernel'?
> 
> >   So, for RHEL3, I would stich with the ia32e kernel, as it has
> > optimizations which are specific to the ia32e processor.  Starting with
> > RHEL4, those optimizations have been integrated into the x86_64 kernel and
> > you'll again have a choice of UP or SMP kernels.
> 
> 
> actually it's the other way around... the x86-64 kernel had
> optimizations that don't work on the em64t cpus so we had to add a
> second kernel without those optimizations..

Arjan,

Does that mean RHEL 4's single x86_64 kernel removed AMD-specific
optimizations so it would run on AMD64 and EM64T?

/Brian/

-- 
       Brian Long                      |         |           |
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