[KLUG Members] SMP and ACPI in 2.6.12

[Chester Wisniewski]

Kevin Mitchell wrote:

> It appears that this happened with 2.6.12-rc6 and that it was
> discussed on the kernel listserv:
>
> http://seclists.org/lists/linux-kernel/2005/Jun/4080.html
>
> I like how the "answer" is "I would think" followed up with "I was
> hoping someone else would comment."
>
> Oh well, perhaps they'll document this requirement a little bit better
> in the next kernel.
>
> Kevin

2.6.12 kernel had some documentation issues resulting from the change in
change management systems... Early changes (pre-rc6?) were not
integrated into the final changelog.

The bigger question is, why would you want to enable hyperthreading?
Have you properly tested your application performance? With the
applications we run our software on it is anywhere from 7% to 18% slower
with it enabled than disabled (on 3.4Ghz XEON CPU's). Its particularly
brutal on database servers.

Chet