Activity Monitor only displays 4 of 8 cores as active

Discussion in 'MacBook Pro' started by kamilski81, Dec 29, 2011.

  1. kamilski81 macrumors newbie

    Joined:
    Dec 17, 2008
    #1
    I have been watching my 'Cpu History' for the Activity monitor over the last few days and I have never seen my computer run on the 'even' cores? I run vm and am a developer so I use my computer pretty intensely, any idea what may be happening here? See my attachment for what im talking about
     

    Attached Files:

  2. macdudesir macrumors 6502

    Joined:
    Jan 16, 2011
    #2
    The "even cores" are hyper threaded cores. They only run when cpu activity is high...from your graph, its not...The attached pic is my activity monitor (macbook air, so two real, two hyper threaded)
     

    Attached Files:

  3. Queen6 macrumors 603

    Queen6

    Joined:
    Dec 11, 2008
    Location:
    Enjoying Better Things
    #3
    download GeekBench and run the stress test that will get 'all" your Core`s burning ;)
     
  4. kamilski81 thread starter macrumors newbie

    Joined:
    Dec 17, 2008
    #4
  5. w00t951 macrumors 68000

    w00t951

    Joined:
    Jan 6, 2009
    Location:
    Pittsburgh, PA
    #5
    It's pretty common knowledge that the Macbook 15" has an i7 Sandy Bridge quad core processor. One physical processor, four physical cores, four virtual cores.
     
  6. macdudesir, Dec 30, 2011
    Last edited: Dec 30, 2011

    macdudesir macrumors 6502

    Joined:
    Jan 16, 2011
    #6
    ...that's somewhat right I guess...they have 4 cores...but each core has two threads...so the OS sees 8 cores and processes as 8 cores. If you do something processor intinsive I garuntee you will see those other cores come on

    EDIT: should have read further in to the link...it does mention hyper threading. sorry :eek:
     
  7. theSeb macrumors 604

    theSeb

    Joined:
    Aug 10, 2010
    Location:
    Poole, England
    #7
  8. thundersteele macrumors 68030

    Joined:
    Oct 19, 2011
    Location:
    Switzerland
    #8
    Technically these are the even cores. Internally they are adressed as core 0,1,2,3,4,5,6,7, so the ones that are active in the screenshot are the cores 0,2,4,6

    It is somewhat surprising that a) you didn't know how many cores your quad core CPU has, and b) you are not familiar with the concept of hyper-threading.
     

Share This Page