Re: NetBSD # actual cores

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Thu, 4 Jan 2024 09:13:17 -0600
    From:        Jason Bacon <jtocino%gmx.com@localhost>
    Message-ID:  <b4566134-0f0e-4d76-a98a-79d5741c9f6b%gmx.com@localhost>

  | Is there a way to detect whether hyperthreading is enabled?  If we have
  | that, we can divide hw.ncpu by 2.

No you cannot.   Not on modern processors.   On my system NetBSD
reports 24 cpus, and hyperthreading is enabled - but  that is not
12 cores, there are 16.  8 of the cores support hyperthreading,
the other 8 do not.

If we are going to implement something like this, do it in a
general way which supports current, and likely future, systems.
Not a hack which just seems like it might work.

kre