Kernel_Task: What Is It & Why It Eats A High Percentage Of CPU

Did you come across kernel_task in the Activity Monitor? Are you wondering what it is? Fortunately, it’s nothing outrageous that you should worry about. It is your operating system. 

A kernel is at the core of any OS. It sits between the memory, CPU, and other software and hardware you are running. When you switch on your Mac system, the first thing that starts is the kernel. At some point, whatever you do on your device runs through the kernel. All these varied activities are put under Mac Activity Monitor kernel_task.

Is your Mac lagging? If so, there’s no need to worry about the kernel taking up a lot of memory or eating CPU cycles. kernel_task uses unused memory for activities, such as running a modern OS and caching files. Therefore, sometimes, it utilizes some CPU power. However, if you encounter kernel_task taking up many of your system’s resources and your device is performing slowly, you may have a problem. One way to fix the issue is rebooting your Mac, which will automatically restart the kernel.

Why Is Kernel_Task Eating Up So Much CPU?

kernel_task processes are not truly using the CPU cycles but preventing them from being utilized. In this process, the CPU is getting throttled. 

Throttling the performance of the CPU is an effective and common way to prevent overheating. It is likely that your Mac’s fans are running if kernel_task is running. If you hear fan noises and find kernel_task in the Activity Monitor window, it is logical to think that the problem is the kernel_task. However, in reality, it is the symptom and not the problem. 

When kernel_task uses most CPU cycles, it means another program or process is stressing out the CPU and resulting in your system running hot. That process might be something you’ve chosen, like encoding video files, or it is a rogue process running because an app has run into problems. 

For instance, Adobe Flash was a common culprit causing CPUs to overheat and forcing kernel_task to use up CPU cycles. But it is less common now because Flash is removed from most Macs.

How To Reduce CPU Usage And Fix The Kernel_Task Issue?

  • Reboot Or Restart Your Mac System

Restarting your Mac will refresh the OS and close services and applications functioning in the background. These processes are sometimes the culprits that pressure the system’s processor. The CPU usage of kernel_task should reduce after you’ve restarted Mac. 

  • Close Processes And Programs Via Activity Monitor

Want to find out the reason behind the high CPU usage? Head to Finder > click Go > select Utilities > click to open Activity Monitor. Here, you’ll find the active processes displayed in real-time, and you can choose the CPU tab to find out their CPU usage. It will be ranked from the highest to the lowest. You need to choose the processes with high CPU usage and click the X button to close them. 

  • Boot Your Mac And Start In Safe Mode

By starting your Mac in Safe mode, you can determine if kernel_task’s extremely high CPU usage is due to third-party software. 

You need to check if your Mac has an Apple or Intel CPU. Once you have found that, follow these steps. 

  • If your Mac has an Intel CPU, you need to click the Apple logo > select Shut Down and wait ten seconds. Then, you need to restart your Mac and immediately press and hold the Shift key. You need to release the key and log in when you see the login window. 
  • If your Mac uses an Apple CPU, you need to go to the Apple logo and choose Shut Down. Then, wait for ten seconds and restart your system. Until startup, you have to press and hold the power button. Release the button when you see the startup options window. Then, you have to choose a startup disk. Press and hold the Shift button and select Continue in Safe Mode. Release the Shift key after that and log in. 

If you want to exit Safe mode and start your Mac normally, you need to restart your system without pressing or holding any keys.

  • Reset The NVRAM

Non-volatile random-access memory or NVRAM is computer memory capable of holding data when power to the memory chips has been switched off. You can restore kernel_task’s CPU usage to regular levels by resetting the NVRAM. You need to switch off your system and wait for your computer to shut down completely. Then, tap the power button and when you hear the startup sound, hold Option + Command + P + R keys. Hold the keys until your system restarts.

So, here’s what you need to know about kernel_task, and as you can see, there’s nothing to worry about.