Kernel_task high memory usage

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Kernel_task high memory usage

So I have a mid-2015 macbook pro retina (2.5 GHz Quad-Core Intel Core i7, 16 GB 1600 MHz DDR3, Intel Iris Pro 1536 MB) running macOS Big Sur v11.1, which has started running extremely slowly. The fans are contstanly on high, even just after login when there are no applications running, the trackpad and keyboard are slow to respond, when moving across the dock the magnification of the apps is super slow and jagged and it takes an eternity to open just about any program. I'm certain this is down to the kernel_task running super high CPU% (565%) and it's virtual memeory usage (197GB) as shown on the screenshot below.

I have tried a number of fixes, I've checked through the ktexts (I think that's what it was called off the top of my head) in terminal and there are no 3rd party process running there, I have updated to macOS Big Sur (I've also tried re-installing it) and I've reset both SMC and PRAM.

Any help would be appreciated.

MacBook Pro 15″, macOS 11.1

Posted on Jan 11, 2021 4:04 AM

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Answer 1

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thurs2 Author

Level 1

10 points

Jan 17, 2021 12:09 PM in response to KMB_12

Hi Kareng12,

Booting in safe mode made no difference at all, still massive memory usage by kernel_task.

I created a new admin user and booted in there, the system was still running extremely slowly (fans were still running high too), but strangely there was no kernel_task visible in the activity monitor. I also tried booting in safe mode under the new user with the same result.

It’s becoming so bad I’m replying on my phone because I can’t load a browser on my Mac...

Cheers,

Harvey

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Answer 2

KMB_12

Community Specialist

Jan 16, 2021 1:12 PM in response to thurs2

Hi thurs2.

The battery info actually looks fine in terms of cycle count. In fact, for a 5-year-old Mac, the count is fairly low. There are a couple of steps you can take that may help isolate this to either hardware or software.

1) Start by doing a safe boot of the Mac. This will clear some cache files, turn off some system extensions and log-in items and give you a good foundation. After doing the safe boot, reboot normally and test.

How to use safe mode on your Mac

2) If the issue persists after a safe boot, set up a new admin user account and boot into that for testing. Doing so helps you to isolate the issue to the system or the user data and ultimately resolve it.

You can find the steps to add a user here:

Set up users, guests, and groups on Mac

Cheers.

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Answer 3

Jan 18, 2021 2:08 PM in response to thurs2

Hi thurs.

As noted earlier, the kernel_task process ramping up (it's always running, but under normal circumstances takes a very small amount of CPU) is often a response to heat. The fact that it is not immediately registering high in a test user while the fans continue to run high is strongly indicative of a hardware issue. Your next best step is going to be to have someone physically inspect the Mac.

Contact Apple for support and service

Cheers.

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Answer 4

thurs2 Author

Level 1

10 points

Jan 13, 2021 7:48 AM in response to SnickZ.

Hi SnickZ, thanks for the reply.

I've not really had any issues with heat, in fact it rarely gets hot anymore (although that's partially becuase it's pretty unusable at the moment.

I've checked what you suggested, seems to be fine to me, see the screenshot though it might mean more to you than it does to me :)

Cheers,

Harvey

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Answer 5

SnickZ.

Community Specialist

Jan 13, 2021 6:29 AM in response to thurs2

Hello thurs2 and welcome to Apple Support Communities. It appears you are having some difficulty with kernel_task consuming tons of CPU and slowing down your Mac.

This process most often ramps up as a kind of self-protection measure when the Mac is running hot. Check at About This Mac > System Report > Power > Battery. The thing that most often causes excess heat is a battery near the end of its functional life

Cheers.

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Kernel_task high memory usage

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