Turn off hyperthreading on dual core Atom?

RW rwmaillists at googlemail.com
Mon Aug 29 22:56:55 UTC 2011

On Mon, 29 Aug 2011 15:15:02 -0600
Brett Glass wrote:

> At 01:55 PM 8/29/2011, Bruce Cran wrote:
> >Actually, the ULE scheduler does know about HyperThreading and the 
> >topology of such CPUs. I don't know what it does with the 
> >information, but it probably works to optimize cache usage etc.
> Alas, during a recent kernel build, I used the -j2 command line 
> option in "make" and watched as the scheduler repeatedly assigned 
> two instances of cc (the most CPU-intensive program) to the same core.

Doesn't that make sense. If the scheduler can't put two threads from
the same process on a core, it puts two processes running in the same

BTW I thought hyperthreading was off by default on security grounds.

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