Scott Long scottl at
Tue Apr 19 11:25:09 PDT 2005

David O'Brien wrote:
> On Tue, Apr 19, 2005 at 11:59:53AM -0600, Scott Long wrote:
>>David O'Brien wrote:
>>>On Sat, Apr 16, 2005 at 01:03:31PM +0200, O. Hartmann wrote:
>>>>I have ASUS A8N-SLI Deluxe mobo. BIOS revision is 1006. I have no 
>>>>problems with
>>>>ACPI. APIC works with NO_MIXED_MODE commented out in kernel.
>>>Disable the NO_MIXED_MODE option is a performance degradation.
>>>Bending over and taking it up the a** across all motherboards (which DES
>>>has forced on 5.4-RELEASE); makes the ASUS A8N-SLI Deluxe not "perfectly
>>According to the APIC maintainer, and according to some quick benchmarks 
>>myself, mixed mode has almost no performance impact.
> Maybe with the latest code - if you're talking about before the very
> recent jhb commits.  Peter has said several times there is(was) a
> performance issue.  'mixed mode' also is (was?) expressly prohibited by
> the ACPI spec.  

Mixed mode had a performance impact back in the 5.1 or 5.2 timeframe 
when the PIC/APIC code wasn't abstracted like it is now.  This applies
to 5.3 and 5.4.  6.0 will of course be better since the factors that
make mixed mode a consideration are now solved a different way.


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