What is Kernel_task? How to fix kernel_task error taking CPU on macOS

Suddenly you find something called kernel_task in the Activity Monitor application without knowing what this is. The good news for you is that it's not something bad, it's your operating system kernel.

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Kernel - is the core of any operating system, located between the CPU, memory and other software and hardware you are running. When you turn on the Mac, the kernel is the first to boot. Basically, everything you do on the computer must go through the kernel at some point. Activity Monitor puts all other activities under one banner with the kernel-task name.

If your computer is not working slowly, don't worry that this process will consume memory or use CPU cycles, which is normal. Unused memory is easily wasted, so kernel_task will work for caching files and running the modern operating system, meaning that sometimes the CPU power must be used.

However, if kernel_task continually uses most of your system resources and causes the Mac to be slow, you may have a problem. Try restarting the computer because this is the only way to re-run the kernel, maybe it will solve the problem. But if this situation continues, here are some useful information for you.

Kernel_task uses the CPU cycle to keep the machine cooler

If you're doing something that takes up a lot of processing power like 4K video conversion, you might be wondering what makes this process so time consuming. Normally, when looking at the Activity Monitor, you will see the kernel_task using the CPU - the amount of CPU you are trying to use for your work.

You are disappointed, but your operating system does this in order to prevent the CPU from heating up.

One of the functions of kernel_task is to help manage the temperature of the CPU by making the CPU unavailable for processes that need to use it a lot. In other words, kernel_task resolves the causes of the CPU heating up even if you don't feel the Mac is hot. When the CPU temperature decreases, kernel_task will automatically reduce its operation.

Therefore, kernel_task does not really use up the CPU capacity: it only prevents activities that use too much to make the CPU hot. Everything will return to normal when you exit the CPU-consuming programs.

One of the most CPU-intensive applications is Flash. If you see Flash or browser tabs taking up a lot of CPU and kernel_task, consider uninstalling or disabling Flash completely to avoid an unfortunate problem. This will free up CPU capacity and make the machine cooler.

Boot into Safe Mode to fix kernel problems

If you see kernel_task using too much CPU or memory while you are not using many programs, you may have encountered another problem. Typically, this involves third-party kernel extensions, called macOS called kexts. These modules come with hardware drivers, some software and interface directly with the kernel. Kext errors can cause kernel_task to occupy a lot of system resources.

To test, you should boot Mac in Safe Mode, one of the hidden Mac boot options that users should know. Turn off Mac, then turn on and hold Shift. You will see from Safe Boot in the login screen.

Safe Mode does not allow third-party kext, so if your Mac has no problem running in Safe Mode, you have found the problem. Remove software or third-party drivers that you have recently installed to help.

You can use error scanning software - Etrecheck, this software includes a list of all kext installed and running on your system. Remove programs that you think cause problems and see if they can be resolved. If not, you need access to Apple Store or a reputable Mac repair shop near your home.

You can try a few other ways

If you still get errors later, you can try some of the following:

Resetting NVRAM on a Mac will probably help or consider scanning malware on the Mac because this could be the cause of the problem. You can also do some things like remove unnecessary startup items and free up hard drive space to speed up your Mac.

If the above methods are not effective, you should reinstall macOS from scratch. This is the last resort.