7

My CPU has 2 cores, so I can see two parts in /proc/cpuinfo.

But, I want to know if CPUs that support Hyper-Threading (or similar tech), will /proc/cpuinfo give CPU info per core or per thread (or call it sibling)?

I only know that Windows Task Manager will give CPU usage statistics per thread if the CPU supports HT.

1
  • Also there's no /etc/cpuinfo.
    – bdonlan
    Jul 18, 2011 at 2:44

2 Answers 2

7

The contents of /proc/cpuinfo contains information for all processors down to the virtual level.

Here are some tips on interpreting the contents:

  • Each physical processor will present as at least one processor
  • Each core will present as at least one processor
  • Each hyperthread will present as one processor.

Thus, a dual-socket, dual-core, hyperthreaded system will show as 8 processors. A similar quad-core system will show as 16 processors.

Within the content of /proc/cpuinfo each logical processor has its own ID. If your system is SMP then it will also have a physical id. This is naturally the physical processor number. If you have a multi-core processor then each logical processor will also have a core id. Core ID's are only unique within a single processor. I.e, physical 0 will have core 0 and core 1, and physical 1 will also have core 0 and core 1.

3

Hyper Threading would appear in /proc/cpuinfo as separate processors. So if your CPU have 2 cores each with hyper-threading enabled then /proc/cpuinfo would show 4 processors.

Hence as you describe your configuration, hyper-threading is either not available, or it is not enabled in the bios.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .