Core Duo - only one cpu being used

Attila Nagy bra at
Fri May 5 13:03:51 UTC 2006


On 05/05/06 06:44, Scott Long wrote:
> CPU1 is being treated as a hyperthreading core instead of a real core, 
> and is being disabled per our policy on Intel hyperthreading.  By 
> 'disabled' I mean that it is started, but it is being excluded from
> scheduling decisions, and thus is only running its idle proc.  It's
> also handling any interrupts that come to it, such as timer and IPI
> interrupts, so it's at 99% instead of 100% for the idle proc.  There
> is nothing broken about the number you are seeing, your system is
> just running under a scheduling policy that it should not be.
> This should have been fixed a week or so ago by a commit to HEAD,
> RELENG_6, and RELENG_6_1 by Colin Percival.  How old is kernel?
Isn't this fixed by jkim's commit?

I don't have any Core Duos here, but on a Xeon LV (Sossaman) with 
CURRENT, everything is OK:

BTW, just set machdep.hyperthreading_allowed=1 until the fix arrives.

Attila Nagy                                   e-mail: Attila.Nagy at
Free Software Network (FSN.HU)                 phone: +3630 306 6758

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