1. OCAU Merchandise is available! Check out our 20th Anniversary Mugs, Classic Logo Shirts and much more! Discussion in this thread.
    Dismiss Notice

cpuinfo wanted for p/e-core config CPU

Discussion in 'Other Operating Systems' started by akashra, Jun 26, 2022.

  1. akashra

    akashra Member

    Joined:
    Apr 25, 2003
    Messages:
    3,992
    Location:
    Melbourne, AU
    I've done a bit of a quick google but didn't find anything, thought perhaps someone who owns an Intel 12-series CPU could help me here - can you paste for me (maybe use a pastebin as the output is likely to be long) the full output of `cat /proc/cpuinfo` - I'm looking to see what identifiers there might be to help me if I were to use a 12-series CPU in a kubernetes cluster/VM, some ansible scripts, and on some docker containers.
     
  2. GumbyNoTalent

    GumbyNoTalent Member

    Joined:
    Jan 8, 2003
    Messages:
    10,532
    Location:
    Briz Vegas
  3. OP
    OP
    akashra

    akashra Member

    Joined:
    Apr 25, 2003
    Messages:
    3,992
    Location:
    Melbourne, AU
    Huh? That's a sample output of a single Xeon core. How would that help here when I'm after the details seen by the OS of the core-configuration from each of the P- and E- cores specifically on the 12-series CPUs?
     
  4. Yehat

    Yehat Member

    Joined:
    Aug 4, 2002
    Messages:
    663
    Location:
    Melbourne
    Last edited: Jun 26, 2022
  5. GumbyNoTalent

    GumbyNoTalent Member

    Joined:
    Jan 8, 2003
    Messages:
    10,532
    Location:
    Briz Vegas
    Each thread/cores is given a unique ID called apcid, everything else is usually identical as they are all the same, hyperthreaded CPUs core id is the core match so you can match the thread/core with the physical core. All combinations of core id and apcid will be identical in a intel cpu. Interestingly (if your interested) ARM is usually a mix and the different cores are actually identified by physical id because they are actually a seperate CPU, I don't have any ARM based boxes at the moment.

    This information is of a physical CPU, virtual are different again but treated the same by the kernel.

    NB Notice how processor doesn't match apicid on intel/hyperthreaded CPU, I believe they line up on non hyperthreaded CPUs like AMD.

     
    Last edited: Jun 27, 2022
  6. GumbyNoTalent

    GumbyNoTalent Member

    Joined:
    Jan 8, 2003
    Messages:
    10,532
    Location:
    Briz Vegas
    From Yehat post, 24 CPUs and 16 Cores would suggest that 8 cores are hyperthreaded and 8 are not, so matching the core id with 2 associated apcid will be the P cores while the E cores will only be a 1 to 1 association.

     
  7. OP
    OP
    akashra

    akashra Member

    Joined:
    Apr 25, 2003
    Messages:
    3,992
    Location:
    Melbourne, AU
    Yeah, that's kinda what I'm looking for - I believe lscpu will also provide something similar. It therefore looks like I have to parse the output of either command and look for the elements where the apcid has more than one child and only pass that coreid to be utilised by the target host vm.

    That's why I want to see what it looks like as a *full* output of the command, not just one or two samples of the individual core output.
     
  8. Quadbox

    Quadbox Member

    Joined:
    Jun 27, 2001
    Messages:
    6,679
    Location:
    Brisbane
    No help for ansible etc, but if you're using slurm on your kubernetes cluster, doesnt slurm allow you to schedule based on hyperthreading cores or not? I could have sworn I've done that before on my uni's supercomputers
     

Share This Page

Advertisement: