Turn off hyperthreading on dual core Atom?

Adam Vande More amvandemore at gmail.com
Mon Aug 29 21:20:48 UTC 2011

On Mon, Aug 29, 2011 at 4:15 PM, Brett Glass <brett at lariat.net> wrote

> 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.
> During that process, I also watched CPU utilization in top(1). The peak was
> 46% idle, which means that HTT appeared to be making at most a 4%
> difference. (If the peak were 50% idle, HTT would be doing nothing at all,
> because top(1) can't tell that there aren't really 4 CPUs.)

You can achieve definitive answers by timing several build runs of each
setting and using ministat.

Adam Vande More

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