How to turn off a core?

Discussion in 'MacBook Pro' started by squwish, May 26, 2007.

  1. squwish macrumors member

    squwish

    Joined:
    Apr 17, 2007
    Location:
    STL
    #1
    How do I turn off and on a core in my macbook pro?
    For some reason I thing one of the cores have been turned off.
    Please help.
    Thanks
     
  2. chex macrumors regular

    Joined:
    May 17, 2007
    #2
    its not possible to do either, why do you think one of them is 'off'
     
  3. squwish thread starter macrumors member

    squwish

    Joined:
    Apr 17, 2007
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    #3
    My computer is very very slow when I'm trying to render out 2 movies H.264 videos at the same time...
     
  4. mkrishnan Moderator emeritus

    mkrishnan

    Joined:
    Jan 9, 2004
    Location:
    Grand Rapids, MI, USA
    #4
    Actually, there is a tool in the developer tools that can turn off a core, but it's not something that just happened to your mac by accident.

    Are you using Handbrake? I was under the impression that the current release version has some limitations that are being worked on regarding performance on multiple cores. There are threads about this here, I think. Before you conclude that a core is off (which I would think something like iStat can tell you pretty easily), I would also look at threads related to speed on the app you're using and how well that app handles multiple cores.
     
  5. squwish thread starter macrumors member

    squwish

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    #5
    yeah, see when I look at iStat, it only shows the temp for CPU A. I am not using hand break but I use Final Cut Studio 2 for rendering film.
     
  6. Shaduu macrumors 6502a

    Shaduu

    Joined:
    Jan 31, 2007
    Location:
    Southsea
    #6
    iStat will only give you one temperature because the C2D chips only have one temperature sensor.

    As for speed, have you tried looking at your processes in Activity Monitor? When your Mac gets slow, have a quick check on your processes/pageins/pageouts to see if there's anything unsuspected there.
     
  7. squwish thread starter macrumors member

    squwish

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    STL
    #7
    There is this program called UnrarX which is running in the background( at 98%) I found the problem.

    thanks
     
  8. mkrishnan Moderator emeritus

    mkrishnan

    Joined:
    Jan 9, 2004
    Location:
    Grand Rapids, MI, USA
    #8
    Sorry, iStat was a bad example. You're correct, the cpu temps tell you nothing. I was thinking of the activity component of it. Probably the easiest way is to open activity monitor, run *several* apps that consume significant resources, and watch where the (total) CPU allocation goes. If it adds up to more than 1.0 / 100%, both cores are working. That way does work, doesn't it?
     
  9. squwish thread starter macrumors member

    squwish

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    STL
    #9
    that does make sense but that means that 200% = 2 cores? wait, I'm lost.:confused:
     
  10. Shaduu macrumors 6502a

    Shaduu

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    Jan 31, 2007
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    #10
    That's exactly right; 100% CPU usage is a single core.
     
  11. mkrishnan Moderator emeritus

    mkrishnan

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    Jan 9, 2004
    Location:
    Grand Rapids, MI, USA
    #11
    You shouldn't necessarily expect 200% utilization, however, unless you're either using a program that's very good at multi-core usage, or running several programs that can be assigned to different cores. But it should be well above 100.
     
  12. flopticalcube macrumors G4

    flopticalcube

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    #12
    Activity Monitor in the CPU tab will show both cores' activity in the lower right-hand graphs.
     
  13. NJuul macrumors 6502

    Joined:
    Mar 15, 2006
    Location:
    Boston
    #13
    You can use ministat2 (a small widget) to monitor the load on each processor core.
     

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