MBP '11, i7 working as single core?

Discussion in 'MacBook Pro' started by OngL, Apr 4, 2011.

  1. OngL, Apr 4, 2011
    Last edited: Apr 4, 2011

    OngL macrumors member

    Feb 17, 2009
    I have just bought MBP '11, 17", i7 (4 cores). I understand the Intel i7 has four cores and Snow Leopard has the technology to spread load into CPU cores even if the App doesn't support it.

    Here some conditions that puzzled me:

    1) iStat Menu, displayed 7 instead of 4 cores. I presume, it 'wanted' to display 8 which is 2 for each core but missing one somehow. Why the four cores are being displayed as 8 cores?

    2) I used Super Flexible Sync to transfer my data back to the new HDD. The CPU intensive operation during file sorting/listing and copying seems revolved only around the first core i.e. 90-100% and the rest of the 3 cores are showing minimal activity from iStat menu display. The fans are buzzing, CPU temp goes to 78 degrees celcius with internal fan at 5k RPM plus external fan cooling the MBP.

    CPU 1: 90 degrees C
    CPU 2: 83 degrees C
    CPU A: 85 degrees C
    Fans: 4k RPM with additional external fans cooling the keyboard/hinge area

    CPU load: 12% used, System 1%, Nice 0%, idle: 87%
    CPU Core 1: up to 100%, the rest of the cores just 10% or less.

    At this point, I thought Snow Leopard should have distribute the load into multiple core even if the App doesn't support it?

    3) Apart from having Super Flexible running, I also compress my files using 'Clusters'. Again, only first core is active and the rest cores are sitting almost idle. At this point, I'm not getting the multicore idea... At least my MBP 2008 with dual core are showing really high CPU activity on both cores if this is the case.

    3) How do I know when Turbo function actually kicks-in? Doesn't seems to have this working at all. I recalled that turbo kicks-in if there is a high load and the operating temperature allows it to operate at higher clocks.

    4) I'm most of the time connected to A/C power. In the past with detactable battery, It is recommended to remove the battery if this is going to be connected to power source for a very long period. Now with built-in battery, it is not practically possible to remove the battery while on power source. Does it have detrimental impact being connected to power source for long period of time as it was in older MBPs?

    5) Lastly, I am using OWC SSD with upgraded MP4 firmware. I can't seems to be my system to hibernate and it hangs when waking up from sleep. any idea?
  2. Hellhammer Moderator


    Staff Member

    Dec 10, 2008
    1. Hyper-Threading. Each core supports two threads.

    2. Snow Leopard can't help if the app does not support multithreading. It added GCD which made it easier for devs to include multicore support but it's not always that simple, especially when dealing with more complex apps.

    3. MSR Tools might help.

  3. OngL thread starter macrumors member

    Feb 17, 2009
    In the case of the application doesn't support multicore, it always goes to Core 1? So if I run 5 apps that can only support single core, my CPU Core 1 will be jam-ed up and the rest of the core idle?

    Just wondering why these single core apps are not distributed to idle core e.g. not spread across cores but assigned different cores.
  4. Hellhammer Moderator


    Staff Member

    Dec 10, 2008
    OS X should distribute the tasks to cores evenly. If app #1 is maxing out core #1, then running app #2 should not tax the core #1 but some other core.
  5. TheUndertow macrumors 6502

    Feb 20, 2011
    If its not a multi-core app, my understanding is it has the ability to increase speed/performance to the single core, and for those apps that weren't made to take advantage of the multi-core processing.
  6. OngL thread starter macrumors member

    Feb 17, 2009
    This seems isn't the case with 10.6.7, MBP 2011. I have now a fully utilized core 1 and idle core 2-4. The overall CPU usage is 13%, but temp and fans are going crazy. In core #1 CPU is 100% used.
  7. Exana macrumors regular

    Mar 15, 2011
    I got this with my MacBook Pro 15” Core i5 2010 : 4 cores and 4 graphs


    My MacBook Pro 15” Core i7 2011 : 8 cores but only 1 graph like a one CPU unit.

    I have to click the graph to see the 8 cores activity.
  8. ghostlyorb macrumors 6502a


    Jan 9, 2010
    Virginia, USA
    Well.. what all are you running? Why are you complaining about one core being used?

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