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Problem with Kernel Task - El Capitan

Since I have upgraded my MacBook Pro to the new OS, when it is unplugged, the Mac slow down and the Cpu usage is from 120 % to 300 % ( the process is Kernel Task).. What can I do?

Thanks a lot

MacBook Pro (13-inch Early 2011), OS X El Capitan (10.11)

Posted on Oct 1, 2015 2:02 PM

Reply
94 replies

Dec 24, 2017 10:24 PM in response to Badgermonkey

Hello! I know you comment was made awhile ago, but was hoping you could help me.


I followed the steps you listed but I can't find Resources! (What I see instead when I go to

/System/Library/Extensions/IOPlatformPluginFamily.kext/Contents/PlugIns/ACPI_SMC_PlatformPlugin.kext/Contents/)

User uploaded file

I have done something similar to another OS (Yosemite) and it worked fine so not sure what's wrong here.


Please help! Thank you!!

Jun 4, 2017 5:36 PM in response to Linc Davis

I just started having this problem -- kernel_task is using around 250% CPU. Can it be due to running the computer with no battery at all? Surprisingly, I don't hear the fan going.


I took my 2011 MacBook Pro to an authorized service provider to get the battery replaced (the computer was shutting down at 30%). They didn't have a replacement battery, but the tech noticed that the battery was swolen, and wouldn't put it back in because he said it could start leaking and damage the computer. He said it would be OK to run on AC.


I did an SMC reset yesterday (before removing the battery today -- I was on chat with Apple Support and they recommended it when we were doing initial trouble-shooting of the battery depletion problem).


Should I try BadgerMonkey's procedure?

Jan 26, 2018 8:43 AM in response to Badgermonkey

just to say THANK-YOU Badgermonkey! 🙂


working on a MacBook Air (13-inch, Mid 2011) El Cap swapped the battery out (initially for another used one, just to charge it) and the computer went into SUPER S L O W mode 😮


couldn't figure out why, never seen this before 😕


wouldn't boot off USB, wouldn't clean install off USB.

Finally clean installed via Thunderbolt & Target Mode but still wouldn't run at normal speed under its own steam.

Would ONLY boot in safe mode and run fine.


stumbled upon your post...


removed MacBookAir4_2.plist

and BOOM! my problem solved 😮


THANKS AGAIN!


MacBook Air (A1369), macOS Sierra

Oct 1, 2015 4:03 PM in response to amico96

The kernel is using excessive processor cycles. Below are some possible causes for the condition.

Throttling

When it gets high temperature readings from the hardware, or low voltage readings from the battery of a MacBook, the kernel may try to compensate by interrupting the processor(s) to slow them down and reduce power consumption. This condition can be due to:

☞ a buildup of dust on the logic board

☞ high ambient temperature

☞ a worn-out or faulty battery in a portable

☞ the malfunction of a cooling fan, a temperature sensor, a voltage sensor, or some other internal component

Note that if the problem is caused by a sensor, there may be no actual overheating or undervoltage.

If the computer is portable, test with and without the AC adapter connected. If kernel_task hogs the processor only on AC power, charging is causing the machine to heat up. That behavior may be normal for some models, but it may also be an indication of a hardware fault.

Apple Diagnostics or the Apple Hardware Test, though not very reliable, is sometimes able to detect a fault. For more thorough hardware testing, make a "Genius" appointment at an Apple Store, or go to another authorized service provider.

If nothing is wrong with the hardware, then whatever you can do to improve cooling may help.

Installed software

User-installed software that includes a device driver or other kernel code may thrash the kernel. That category includes virtualization software, such as Parallels and VMware, as well as most commercial "anti-virus" products. Some system-monitoring applications, such as "iStat," can also contribute to the problem. You can test for this possibility by completely disabling or removing the software according to the developer's instructions, or starting in safe mode. Note, however, that disabling a system modification without removing it or testing in safe mode may not be as easy as you think.

Corrupt NVRAM or SMC data

Sometimes the problem is cleared up by resetting the NVRAM or the SMC.

External display

Connecting an external display to some MacBook Pro models while the lid is open may cause this issue. If applicable, use the external display in clamshell mode.

Oct 3, 2015 6:25 PM in response to Linc Davis

Thanks Linc Davis! This is really helpful. Assuming the kernel_task issue is due to a software installation, what is the fix for it?


Any additional help would be much appreciated, and thank you!


TL;DR

I can't just do without the likely software culprits such as vmware (I've also been suspicious of R and LaTeX). My kernel_task is currently running 1.34GB of RAM at 136 threads (and no change over the course of writing this post).


As for the other possibilities, this happens to my MBPro (and the MBAir before it) regardless of external display connectivity, regardless of the fact that I have reset the NVRAM & SMC controller on numerous occasions with no improvement, and temperature isn't an issue due to good environment. I should note that this often happens when I come back to the computer after it's been sleeping for some indistinguishable period of time. When I acquired the MBPro, I set it up from scratch without using Migration Assistant.

Oct 28, 2015 12:05 PM in response to amico96

I had this issue with a previous upgrade and this fix worked great. However, in El Cap this is a protected system file. In order to delete it you need to:

0. Reboot into recovery mode (Command + R on boot prior to startup chime), select Utilities/Terminal, csrutil disable <Enter> (repeat process, use csrutil enable after removing the file), reboot.

1. Go to About this mac under the apple in the upper left and click on More info

2. Click on system report

3. make a note of what it says after Model Identifier (MacBookPro8,2 is mine).

4. From the Root drive (not home folder): – System Library – Extensions – IOPlatformPluginFamily.kext (alt-click/View Contents) – Plugins – ACPI_SMC_PlatformPlugin.kext – View Contents – Resources -– find the name from step 3 and move it to a folder that you can find again if needed.

3. Restart and youÂ’re done (other than enabling SIP).

I can use my Mac again!

Late 2011 15", i7 2.2, 16GB 1333, 1TB hybrid drive, OSX 10.11.1

Problem with Kernel Task - El Capitan

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