How to Fix the Kernel_task High CPU Issue on Your Mac?

It's troublesome once your Mac starts to run slowly, your MacBook Pro is overheating, or the Mac fan sounds so loud. You may consider it is caused by running too many apps simultaneously or running the Mac computer too long.

However, turning off all the apps or even restarting the Mac changes nothing. The slow computer probably has the kernel_task high CPU usage issue. If you ignore it, your Mac may experience crashes or even won't boot up later.

Here, in this article, we offer you the most efficient solutions to fix the kernel_task high CPU usage problem on your Mac.

How to fix your Mac's kernel_task high CPU usage?

• 1. Cool your Mac
• 2. Quit inessential processes in Activity Monitor
• 3. Reset SMC
• 4. Reset NVRAM
• 5. Reboot Mac in Safe Mode
• 6. Update software

What is kernel_task on a Mac?

Kernel_task is a label in the Activity Monitor utility on a Mac. It represents various activities that proceed flows through the kernel (The kernel is at the core of an operating system).

Whenever you turn on your Mac to play a game, or edit some documents, or so, it will trigger a series of system activities. To consolidate these various activities, the Activity Monitor named them kernel_task.

How to check the kernel_task CPU usage on your Mac

You need to launch Activity Monitor first. Press the Command + Space keys to open Spotlight Search and type "activity monitor" to open it. Or if Spotlight is not working, you can open Finder > Applications > Utilities > Activity Monitor.

Then, select the CPU tab in the Activity Monitor window and type kernel_task in the box at the upper right corner to locate the kernel_task process.

Usually, kernel_task takes up less than 10% of the CPU. And sometimes, it reaches up to 60%. It's also okay.

But when the kernel_task takes up nearly 100% of your CPU or over and continues from minutes to hours, it indicates that the kernel_task of your Mac takes up high CPU usage. Meanwhile, problems happen, such as your Mac machine running slowly.

What are the causes of kernel_task high CPU usage?

As kernel_task is a label of a series of processes, it's hard to immediately find the culprit that causes your kernel_task with high CPU usage.

After research, we have summarized the common reasons for the kernel_task high CPU usage issue:

• Charge your Mac for a long time.
• Run too many apps at the same time.
• Install a buggy Adobe Flash Player on Mac.
• Enable third-party extensions (or called kext).
• The internal fan of your Mac does not work properly.
• Your Mac is attacked by some malware.

How to fix kernel_task high CPU usage

Unlike other programs that can be force quitted from Activity Monitor, you can't force quit kernel_task on Mac as it stands for a series of activities.

According to the reasons we've analyzed above, you can troubleshoot kernel_task high CPU usage issue through the following solutions and fix the Mac running slow issue.

Cool your Mac computer

Apple has suggested that users should use their Mac devices in acceptable environments with operating temperatures between 50° — 95°F or 10° — 35°C. Otherwise, it will lead to high chassis temperature, and consequently, a high CPU usage to regulate the temperature.

Hence, you can try to disconnect your Mac from charging, unplug the unnecessary peripherals, and move your Mac to a cooling environment. After your computer cools down, check if the CPU usage of kernel_task reduces.

Quit inessential processes in Activity Monitor

Usually, the more programs you run, the more CPU it will take up. Consequently, your Mac slows down. You can open Activity Monitor to quit the inessential processes one by one.

When you quit all the unnecessary apps or programs, shut down your Mac and wait a moment. Then, restart your Mac to check if it gets on the right track.

Reset SMC

SMC (System Management Controller) on your Mac controls power management and hardware like battery, fan, etc. If your fan lasts running at high speed and then brings about the kernel_task high CPU usage issue, resetting SMC may fix it.

Reset SMC on MacBook Pro or MacBook Air:

Reset SMC on iMac and Mac mini:

Reset NVRAM

NVRAM (Non-volatile random-access memory) is a small amount of memory that stores OS-related settings to keep your Mac performing properly and boot up quickly.

When kernel_task consumes high CUP and leads to improper Mac performance, resetting NVRAM may fix the trouble.

Here's how to reset NVRAM:

If you use an Apple M1 Mac, there's no need to manually reset NVRAM. It will auto-resets if needed every time you start up your Mac.

Boot your Mac into Safe Mode

Some software enables third-party extensions for managing hardware. This has the risk of causing kernel_task with high CPU usage.

So, you can boot your Mac into Safe Mode, which only loads the required extensions and drivers.

To boot an Intel-based Mac in Safe Mode:

To boot an M1 Mac in Safe Mode:

If your Mac performs well in Safe Mode, the recently installed third-party software is the culprit. You can remove it from your Mac and restart the computer. Then, your Mac will back to normal.

Update software

It is reported that the kernel_task with a high CPU bug even appears on macOS Big Sur. That's not strange. Commonly, the first version of the new OS always along with some pending bugs.

Or you haven't upgraded your macOS for a long time, resulting in the software not working well with the hardware anymore. Later, problems like kernel_task with high CPU usage pop up. Therefore, proceeding with a software update can fix the bug.

All you need to do is to open System Preferences in the Apple menu. Then, choose Software Update to check if there's any new version released. If there are, update your Mac to the latest version.

The kernel_task high CPU usage problem still exists?

If your computer has already updated to the latest OS version, and the above ways fail to fix the kernel_task taking up a high CPU problem, you have to reset your Mac or reinstall macOS to bring your Mac back to the normal state.