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Re: Non-working CPU cores showing up

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On Tue, 2021-11-30 at 02:30 -0500, Paul M. Foster wrote:
> Folks:
> 
> Here's a curious thing. I have a 10th gen Intel i3 CPU with four cores. 
> When I look at /proc/cpuinfo, it actually shows eight cores. There's a 
> line in the output of each core which is
> 
> cpu cores       : 4
> 
> But there are outputs for each of eight cores, numbered 0 through 7.
> 
> Is it possible that there were eight cores on this CPU, and four of them 
> were non-working (I know it's typical to have non-working cores on a 
> die), and this file shows all the original cores?
> 
> Or does someone have a better explanation?

That each core supports Symmetric Multi-Threading (SMT), AKA
Hyperthreading, so appears to software as two CPUs. This is common for
most modern x86 CPUs. (Though the one I'm typing this on actual 8 CPUs
without hyper-threading).

-- 
Tixy

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Thread

Non-working CPU cores showing up "Paul M. Foster" <paulf@quillandmouse.com> - 2021-11-30 08:40 +0100
  Re: Non-working CPU cores showing up Kenneth Parker <sea7kenp@gmail.com> - 2021-11-30 08:50 +0100
  Re: Non-working CPU cores showing up Tixy <tixy@yxit.co.uk> - 2021-11-30 08:50 +0100
  Re: Non-working CPU cores showing up Felix Miata <mrmazda@earthlink.net> - 2021-11-30 09:40 +0100
  Re: Non-working CPU cores showing up piorunz <piorunz@gmx.com> - 2021-11-30 12:00 +0100
  Re: Non-working CPU cores showing up Eric S Fraga <e.fraga@ucl.ac.uk> - 2021-11-30 12:10 +0100
  Re: Non-working CPU cores showing up Dan Ritter <dsr@randomstring.org> - 2021-11-30 12:50 +0100
    Re: Non-working CPU cores showing up "Paul M. Foster" <paulf@quillandmouse.com> - 2021-11-30 17:30 +0100
      Re: Non-working CPU cores showing up Ken Cunningham <ken.cunningham.webuse@gmail.com> - 2021-11-30 18:00 +0100
        Re: Non-working CPU cores showing up Dirk Neumann <neum_d@yahoo.de> - 2021-12-01 08:40 +0100
          Re: Non-working CPU cores showing up Ken Cunningham <ken.cunningham.webuse@gmail.com> - 2021-12-01 09:40 +0100
      Re: Non-working CPU cores showing up Tixy <tixy@yxit.co.uk> - 2021-11-30 18:20 +0100

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