How to solve kernel_task high CPU usage?

Discussion in 'MacBook Pro' started by fantasticbobski, Feb 14, 2014.

  1. VanessaKing macrumors newbie


    Feb 10, 2016
    Sorry for all of the updates, but I have since moved that kext back and the fan almost immediately started back up. So I opened System Preferences > Keyboard and unchecked the "Adjust keyboard brightness in low light" checkbox, then turned the backlight completely down/off (the F5 key on MBP keyboard). Again, I'm almost completely fan-free, only having a few seconds of fan activity when Photoshop opens, etc.

    This way, when I need to, I can turn the backlight off and then back on when I need it, without having to move the kext back and reinstalling. I'm hoping that, like 10.6 and 10.8, 10.10 will be a better experience and my Mac won't go back to running out of control.

    I don't know if this will work with any other laptop, but if you have a light sensor and use auto adjusting with your laptop's keyboard backlight, try these steps first, before moving ANY kexts.

    I should have said before: MacBook Pro 6,1 (mid-2010), running OS X 10.9.2 (Mavericks).
  2. marielosp macrumors newbie


    Feb 25, 2016
    I was looking for a solution to this problem yesterday and tried to find my MacBook Pro 15 retina (10,1) in the plist without success. Then I saw someone's post saying they had solved the problem by turning off sharing in System Preferences...
    I did this (luckily I don't use this feature often)... and my cpu has been purring like a kitten for the last 24 hours.

    MacBook Pro 15 Retina (mid 2012), OS X 10.11.3
  3. Dimwhit macrumors 68000


    Apr 10, 2007
    I've been having this same problem, and it was driving me crazy. Started a month or two ago. I was going to try the .plist thing, but my model's file wasn't there. But I saw the posts about the dust buildup, so I opened up the bottom of my MacMini and blew out all the dust (which was considerable). Seems to have fixed the problem. so while the .plist thing might do the trick, I'd definitely encourage checking for dust, first.
  4. cemdata macrumors newbie

    Aug 24, 2013
    --- Post Merged, Mar 2, 2016 ---
    This has been impacting me for weeks. Hard to believe it was such a simple solution, but it seems to have solved my problem. Also hard to believe that I can't do simple file sharing without hosing my machine. BTW, mine isn't a MacBook Pro, but rather a MacBook Pro without a screen, keyboard, or trackpad. Mac Mini, 2.6 gHz. My i7 MacBook Pro wasn't showing the same symptoms. And by the way, thank you, thank you, thank you. I was prepared to find a much more sinister problem.
  5. CouchBikeDude macrumors newbie


    Mar 3, 2016
    I've had the same experience as Dimwhit! Also many of the preferences panes wouldn't load. It's all good now, must be a design "feature" to save an overheated CPU.
  6. curiousmike1300 macrumors newbie


    Mar 13, 2016
    I have a late 2011 MBP, and had noticed a recent spike in fan activity.
    kernel_task sat at 25% usage almost constantly.
    My googling led me to this thread - from it, I thought "huh, I wonder if my PC share folders could be related."
    Just so happens a couple weeks back I added PC share folders on my desktop.
    I deleted the shortcuts, and kernel_task instantly dropped to that 4-6% range and my fans are simmered down.
  7. atkhalas macrumors newbie

    Mar 18, 2016
    I cannot find my Model Identifier in that folder.... Mine is Mascbook Air 5.2 and there is no such file!!! Is thgast even possible?
  8. minimacnerd macrumors newbie

    Apr 7, 2016
    Don't know if this will work for ye but I found this worked on my macbook pro the fan noise was v loud, computer got v slow and the kernel task was over 300%. I tried all the fixes listed on every forum online - nothing worked.
    I went into system preferences and clicked on Time Machine - I backed up my computer to an external hard drive and no noise since and kernel task is running at under 5%.
    Hope you get solved :)
  9. Raptor235 macrumors newbie

    Feb 13, 2008
    For anyone else who might have had this issue... I had the same thing last summer and now that's it's getting warmer again today... basically every time I plugged my power charger in the CPU would go haywire... tried the fix here but didn't work...

    What's happening is that the cpu is being throttled because of high temp... I ended up opening the MBP today and found a ton of dust in the fans... I've leaned it out with some high pressure air and back in business! Hope this helps someone
  10. Krafty macrumors 601


    Dec 31, 2007
    La La Land
    This might be my problem, cause I definitely have sharing off and kernal likes to spike almost everytime, even if I'm browsing. Doesn't help that during the day it feels like my room is next door to the damn sun.
  11. whsbuss macrumors 68040


    May 4, 2010
    SE Penna.
    Found my problem. I got a replacement battery for my 15" late 2011 MBP on eBay. $21.75 shipped - yeah that was too good to be true. I had all the kernel_task issues reported here. MBP was just about useless with 1-2% idle CPU. So I ran the Apple Hardware test and it gave me a strange error 4xxx/6/40000005:0 battery.

    I put my original battery back (reason I replace it was a cell was going causing very intermittent shutdowns). Since then all is running very well. I contacted the ebay seller but I don't expect a reply. Seller is premiumbattery2014 in case others encounter the same problem. At this point I will most likely keep this MBP for another year and then just grab a new Macbook or pro.

    Lesson: be sure you don't have a hardware problem before you do the System software stuff. RUN Apple Hardware Test
  12. hbeaulieu macrumors newbie


    May 18, 2016
    So, I understand you don't recommend this procedure? Because I'm not finding the proper Model Identifier file either...
  13. Dopeyman, May 18, 2016
    Last edited: May 18, 2016

    Dopeyman macrumors 6502a

    Sep 5, 2005
    Los Angeles!
    I have the same issue... Kernel_task is using high CPU and my "new" battery isn't charging.

    Even if I disconnect my battery and just use the adapter, I still get that kernel_task high usage.

    I tried the SMC and PVRAM resets. I've even did a fresh install of El Capitan and it still had the issue. I don't wan't to remove that kernel file from the system folder cause that's something "temporary". If that file wasn't necessary, it wouldn't be there in the first place. So that's a no.

    My MacBook Pro is a 2012 15" 2.6/i7 with Samsung Evo 256GB SSD....

    Attached Files:

  14. cflurry macrumors newbie

    Jun 15, 2016

    First, yes I realize that these posts were like 2 years ago. I'm just having this issue though and found this forum. Hopefully I'll be able to find some help though.

    Also, I recognize that I really have no idea what any of the technical aspects are or what they do. I only know what I've read on this forum so I get the gist of what kernel does, and that there are possible issues on just moving files around to fix the kernel_task problem using a lot of CPU power, or whatever. Before I started moving files around though I wanted to reply to your comment and ask how exactly you reset the PRAM and SMC if that is in fact something that would help? I just have no clue how to do that and wanted to try before messing with system files.

    I'd appreciate any help, don't want to really mess up my computer. thanks!
  15. ronitag00 macrumors newbie

    Jun 15, 2016

    I am having the same problem, cannot find Model Identifier - MacbookAir5,2..
    Please let me know if you have figured it out.

    Appreciate it.
  16. ciberyo macrumors newbie

    Jun 17, 2016
    My case, for anyone interested:

    My issue happened to be caused by the fan of the computer (I have a hackintosh btw). The fan grill (sorry if you don't call it "grill", english is not my first language)... the fan grill was full of dust and the chip was being overheated, and the computer was trying to cool it down..

    that was all. I clened it, and my computer works now smoothly... no kernel_task consuming 99% of the memory anymore.
  17. EnlaiC macrumors newbie


    Jun 20, 2016
    I too had the kernel_task issue but couldn't find the profile (I have a MacBookPro11,3) so read the other posts and sprayed some compressed air into the vents between the screen hinges. Voila! My kernel_task went down!! That's nuts! Awesome but nuts. Thanks for posting, everyone!
  18. rco7 macrumors newbie


    Jun 24, 2016
    Does anybody here happen to use an encrypted filesystem on their mac? My kernel_task spikes when doing heavy i/o on the disk and I suspect it's the encryption/decryption process not being hardware-accelerated on my old-arse Macbook.

    Just speculation, though.
  19. A Helper/Need help macrumors newbie

    A Helper/Need help

    Jul 7, 2016
    Hey dude This is what i did (Sorry i don't have images)
    1:Go to activity monitor and search "Kernel task"
    2:Then you will see lots of "md workers"
    3:Clear them all.
    4:now I have 1% of kernel task (10% before)
  20. Yod4, Jul 11, 2016
    Last edited: Jul 11, 2016

    Yod4 macrumors newbie


    Sep 12, 2014
    Followed this advice, dragged "My_Model_Identifier.plist" to the desktop. When I tried to delete it later a popup appeared saying "“My_Model_Identifier.plist” can’t be modified or deleted because it’s required by OS X".

    Had a separate issue with my fans which has now been resolved, so since the file is still in use by the system I figured I'd put it back. However, finder won't let me copy it back into place. I'm guessing something about being in a package within a system folder - when I drag the file to the original "Resources" folder cursor makes an "Ø" sign signifying so. Is there a way to put it back - using terminal ?


    Had to diasble SIP in order to copy back the file. Problem solved.
    Leaving this here in case it helps someone.
  21. gwhiz-of-MDR macrumors newbie


    Jul 28, 2016
  22. peterfconn macrumors newbie


    Jul 29, 2016
    my machine is at a crawl so I have to try something. But down to the last step and Model Identifier MacBookPro11,3 is not on the list. List is

    do I delete one of these?

  23. negativeeffect macrumors newbie


    Aug 4, 2016
    Only just seen this after a very panic-y (haha - made me laugh, get it - panic?) friend called me asking for help and wondered how common these things are!

    Just incase anyone else has done this and needs help recovering and stumbled here from Google, maybe you included a dash after Sudo, or were in a Root Shell, or set up not to copy over the environment on Sudo, because my guess will have been it copied into /var/root, which is ~ for the super user.
  24. Yod4 macrumors newbie


    Sep 12, 2014
    I haven't had this problem for a while but since at some point my 5-year old macbook pro's fans were blasting at full speed due to warmer weather, I took the time to clean them. A lot of dust had gathered in 5 years. It's since running silent. This may or may not be connected to kernel_task using up CPU when running demanding tasks and heating up. Sorry if this doesn't help anyone. Just putting it out there.
  25. dyk95112 macrumors newbie

    Oct 18, 2014
    What kind of a troll reply is that? Why don't you enlighten us? The point being is that you can't tell which process is creating the large kernel_task demand. That's why kernel_task time should be minimized and most work handled in user space where there is more accounting. It's suspicious because the NSA is doing covert spin-dumps on your memory while these human predator trolls are misdirecting everyone. MacOS is broken and has been for some time now. Israel did 911 by the way.

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