kernelmanagerd process causing high cpu usage & battery drain

I was facing the same issue after updating to macOS Big Sur. Even removing Malwarebytes and few more third party app from the applications folder + thrash was of no help. Found and article which mentioned that this KernelManagerd problem is caused by a third-party kernel extension and you may need to look further to find the incompatible software.

You can find it in: Finder > Go > Go to Folder > and type /Library/Extensions into the text field. You will see a list of files with the .kext file extension. You may ignore the following files, if you see them:

AppleMobileDevice.kext

HighPointIOP.kext

HighPointRR.kext

SoftRAID.kext

You can find information on your other .kext files with a google search. I deleted MB_MBAM_Protection.kext, (Leftover Malwarebytes file) the moment i did my %CPU for KernelManagerd went from 70%+ to 0%..

There is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus or security apps on your Mac.  This user tip describes what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community   

For me, it seemed to be an old version of Karabiner Elements. I updated it to the latest version so I could open the app's preferences (as I couldn't open the old version on Big Sur), then uninstalled it. Kernelmanagerd dropped from about 50% to 0%.

Same thing here. My fan is constantly running since I uploaded Big Sur. Slowing down my computer. I called Apple Support and they had no suggestions other than to give it a couple days to see if it works itself out.

This post https://www.reddit.com/r/MacOSBeta/comments/i41fd7/high_fan_use_and_kernelmanagerd/ suggested that Karabiner Elements may have been the problem. The person said that the problem was solved after updating it. I updated it and uninstalled it altogether and now my kernelmanagerd is not even showing up in my activity monitor with it sorted by highest CPU usage. It used to be non-stop at over 70%.

Now my fans are running very quiet.

I'm experiencing same issue! uninstalled a malware program but kernelmanagerd

is still eating up my memory and the fan is running constantly, and getting very hot!!

can i delete kernelmanagerd?

HOW?

thank you...

This kernelmanaged the thing is eating up all of my battery and most definitely locking up the operating of the computer. So how do I remedy this issue it runs constantly in the fan runs high because the computer is getting very hot and it’s not good on my brand new computer!

I have the same issues. I have move to trash malwerbyte and popcorn time but it is still happening. The only third party programs that I have are Horos (using it for viewing medical images, MRIs, CTs) and Tunnel blink (an app from my university).

what should I do? Thanks

This happened to my 2015 MacBook Pro as well. After spending many hours on the phone with Apple and at the Genius Bar, the only thing that worked for me was to erase my Mac and reinstall Big Sur. We tried to just reinstall and it did not work. It requires a complete erase.

I first tried to uninstall by dragging the Malwarebytes from the applications folder into trash, but the icon was still on the very top navigation bar. I went in there and did uninstall from that location and it finally worked. So, make sure you have it 100% uninstalled.

Contact Apple ask for a senior advisor.

I was having all of these issues we uninstall all of this malware in cyber ghost and all this stuff and it was still having issues and we went in to select operating programs and we trashed some folders in three or four different applications then tested it and it worked perfect and then we went one by one and reinstalled malware bites and other programs include including bit defender and there is literally no issues with operating programs eating up valuable operating space.

One suggested solution was to uninstall Malwarebytes, which I did not have installed in the first place. On the contrary I could resolve the problem by installing and running Malwarebytes scan once. Although the scan did not find anything the process 'kernelmanagerd' went back to the usual 1% CPU usage right when the scan completed. Have uninstalled Malwarebytes, but the problem remains solved for me.

I was experiencing the fan/CPU issue and saw a few responses mentioning Malwarebytes. A few years ago, an Apple tech installed a trial of Malwarebytes on my machine to clean up some issues, and I uninstalled it along the way. But - after installing Big Sur, I had the fan/CPU issue and started looking around for the Malwarebytes program. In all the basic searches I couldn't find it, not in Applications, not in any normal search I tried. My tech support SigOt ran a bunch of terminal prompts that uncovered a number of files in this folder path: /System/Volumes/Data/Library/Application Support/Malwarebytes. I had to go in using this path to delete the remaining Malwarebytes files, but it has resolved the fan/CPU issue!

For me, the problem was Palo Alto Network's Global Protect VPN app as it is not compatible with Big Sur. Suffered with high CPU and battery drainage for a few days but problem was resolved upon properly uninstalling it by following the instructions on their website.