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HT1338 Kernel_Task is using up 85% of my CPU, and it's making my computer very slow, and I can't close the application. How can I fix my Mac?

619 Views 11 Replies Latest reply: Mar 11, 2013 8:16 PM by WZZZ RSS
Elizfred Calculating status...
Currently Being Moderated
Mar 4, 2013 4:51 AM

For a while now my computer (MacBook Pro Snowleopard 2.26GHz Intel Core 2 Duo) has been very slow, and the battery gets drained quite quickly. I opened Activity Monitor and I found that the system (in red) was using up a large percentage of my CPU even though I had no programs running. When looking at what application was causing this, it said that kernel_task was using around 85% of my CPU, I can't close the program, how can I solve this issue?Screen shot 2013-03-04 at 8.44.17 PM.png

MacBook Pro, Mac OS X (10.6.8)
  • WZZZ Level 6 Level 6 (11,895 points)

    You can't quit the kernel, that's like staying alive without a heart.


    Uninstall the iAntivirus completely. It's junk and not needed. I think that's what may be causing the problem.

  • WZZZ Level 6 Level 6 (11,895 points)

    Can we have a screenshot of All Processes, without any graphs obscuring the information? Also a screenshot of Active Processes?


    Can you run this small program written by fellow contributor etresoft and post the results?



    Also copy/paste this into a Terminal window (Utilities) and hit return. Please post the results.


    kextstat | grep -v apple


    EDITED: What and how many programs do you have open when this occurs. Can you also post a screenshot of the bottom only of the System Memory tab in Activity Monitor. It will look like this.


    Screen shot 2013-03-06 at 8.19.17 AM.png


    Message was edited by: WZZZ

  • WZZZ Level 6 Level 6 (11,895 points)

    I'm really tired right now and can't give this the attention it deserves and will have to take a much better look tomorrow. But very quickly, I'm seeing iAntivirus as a login item. That would be in Sys Prefs>Accounts>Login Items. Remove it with the minus button. How did you remove iAntivirus? Did you use the uninstaller?


    Also you will need to provide several screenshots of All Process, as it is now, and scrolled down to show everything. The one I'm seeing is showing only a bit of it. Same goes for Active Processes.


    What were all those commands you ran in Terminal for which I'm seeing command not found? You misunderstood what I asked you to enter into Terminal. I'm not seeing that you entered kextstat | grep -v apple  Just use that.


    You are running on very little free Memory, as a result it's writing to the hard drive, this is shown in the Page outs, and that will slow everything down. For everything you're running 2GB RAM is not at all adequate. But the kernel doesn't appear to be using excessive Memory.

  • WZZZ Level 6 Level 6 (11,895 points)

    Try a Safe Boot, Shift at the startup chime, and see if the CPU load for the kernel goes down. Give it much more time to boot than a regular boot.


    Also remove any external devices/peripherals and test.


    Disable the VPN and see what results.


    And besides what I asked just above, create a new account in System Preferences>Accounts and give it admin privileges. Then log into it without opening anything and check to see if the kernel is still consuming as much CPU. If it is see if there's any one process, besides the kernel, from the CPU tab of Activity Monitor that is consuming a large amount of CPU.


    Message was edited by: WZZZ

  • WZZZ Level 6 Level 6 (11,895 points)

    To uninstall openvpn



    Not sure what else to suggest. If it's much reduced in Safe Boot, it's something disabled there, but not in ordinary boot.


    Have a look here to see what is disabled in Safe Boot.



    And there's this article on kernel task using excessive CPU


  • WZZZ Level 6 Level 6 (11,895 points)

    Also if you do a search for "kernel task using excessive CPU" you'll get some hits, including some threads here.

  • WZZZ Level 6 Level 6 (11,895 points)

    Oh no. Don't do that. Those are required for normal operation. Safe Boot is only a troubleshooting mode.

    It disables all startup items and login items (Mac OS X v10.4 or later).

    You were showing these, that's why I suggested uninstalling iAntiVirus and the vpn/private tunnel. But you could also remove Dropbox and SpeedhSyntheseisServer. iTunesHelper is harmless.


    User Login Items:










              PrivateTunnel Tray

    For startup items, have a look in the HD Library. That's the second level Library. But stay out of /System/Library, or ask first.


    This article is meant for help with crashes, but it also details items to look for that might be causing other kinds of issues. Look in #2 Where many culprits are found. But don't start deleting stuff all over the place. Ask first.



    And your idea to look for for recently modified items is good.


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