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From: Wojciech Puchar <wojtek@puchar.net>
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To: "Pokala, Ravi" <rpokala@panasas.com>
Subject: Re: detecting hyperthreading
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dmesg
look at "HTT" CPU capability

On Mon, 9 Mar 2015, Pokala, Ravi wrote:

> Hi folks,
>
> There used to be a sysctl, "machdep.hyperthreading_allowed", which
> indicated whether or not the kernel was using hyperthreaded cores. It
> looks like it was removed sometime between 8 and 9, for perfectly good
> reasons (https://svnweb.freebsd.org/base?view=revision&revision=222853).
>
> That said, is there currently a way to tell at runtime from userland if
> hyperthreading is enabled or not?
>
> Thanks,
>
> Ravi
>
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