What is WindowServer

It is a native service that comes pre-installed on all Mac-based devices. The main purpose of it is to optimize the proper display of graphical elements onto your screen. It uses the CPU power to carry out the image of what you see while interacting with apps, icons, or simply switching some tabs in Safari. This is why it is so essential and irreplaceable for owners of macOS. Although Mac is world-famous for its stability and flawless operation, sometimes users may stumble into a very unpleasant spot – high consumption of CPU resources by WindowServer. As a result, Mac starts becoming sluggish, laggy, or even hard-to-use normally due to the downgraded performance. The same scenario may happen with similar processes like nsurlsessiond, mdnsresponder, mds_stores, hidd, trustd, and syslogd as well.

windowserver high cpu usage problem

The abnormal behavior of WindowServer is likely to be related to one of the above-mentioned processes. You may see some of these processes standing in line with WindowServer eating a high number of resources. In case of a bug, one process can pull other related into a fault. The phenomenon of high CPU usage by one of these processes may range from basic to more complex causes. Many users can fix the issue by shrinking the number of graphical elements working on Mac at the same time. The reason can be a cluttered desktop or multiple screens (especially 4K) connected to a single machine. In rarer cases, the high CPU usage of WindowServer may also be caused by unwanted or malicious behavior running some stuff under a curtain. This guide below will give an expert look at how to lower the usage of CPU by WindowServer and related processes on Mac. The solutions should not take much time to get the desirable result of rolling your Mac back to solid performance.

Download Repair Tool

Download CleanMyMac

There are special repair utilities for Mac, that can solve problems related to file system or app malfunction, virus infection. We recommend you to use CleanMyMac to fix the “WindowServer high CPU usage” problem in Mac.

1. Clear your desktop

In case your macOS desktop is cluttered and has no space for storing more files, you should delete or put them into a couple of folders to free up some space. If you run anything basic on your Mac (open a browser or move any icon), WindowServer will have to refresh all files stored on a desktop using CPU cycles. Freeing some space on the desktop will alleviate this task for the process. Do it and check whether CPU usage has changed. It should remove at least some percent off the consumption tab.

2. Close unnecessary windows

This is another quick and effective way to reduce graphical pressure. By closing unused windows working in the background, you will be able to widen the space for WindowServer to breathe. Try this with needless applications and multiple tabs open inside of a browser. It should help you gain more room for better performance.

3. Disable Visual Effects

The next in line on our list is to disable visual effects. Alike Windows, Mac has similar effects designed to colorize users’ experience with extra visual features. One of them is called the “transparency” effect allowing users to look at blurred content located behind windows through sidebars or menus. For example, if you open a window over the desktop with the “transparency” effect enabled, you will see your blurred wallpapers behind sidebars, menus, or toolbars. Unfortunately, such a visual effect requires WindowServer to involve more graphical cycles leading to pumped CPU usage. Thus, it is recommended to have it disabled in case you deal with the issue. This is how:

  1. Click on the Apple icon on top of the screen and choose System Preferences.
  2. Open Accessibility and navigate to Display.
  3. On the right pane, choose an option called Reduce transparency.
  4. Close the window and check your resource monitor again.

4. Delete unnecessary desktops

Mac has a feature to create multiple desktops and switch between them when needed. Having a bunch of them opened at the same time, means WindowServer will have to eat more CPU resources. Hence, try to reduce the number of them in Mission Control and see how it affects the CPU usage.

  1. Press the F5 button to access Mission Control.
  2. Then position your mouse pointer on any desktop you are willing to close.
  3. Finally, click on the X button to remove one or multiple desktops.

5. Install fresh updates

Mac is great at dealing with problems on a software level. If there is some vulnerability or hardware fault, developers come out with new update releases to fix the issues. We recommend you check if all recent updates have been installed on your Mac. You do this using the following steps:

  1. As we did above, click on the Apple icon and go to About this Mac.
  2. Then choose Software Update and check if some updates are pending.

If yes, install them and reboot your system, and start using your Mac with the same activities you ran to see whether CPU usage has changed.

6. Disable external monitors

Some users reported that WindowServer explodes with aggressive CPU consumption only when having a third-party monitor connected. Such an issue persists even on Macbooks with M1 chips and the latest Big Sur version. The critical solution is to disable an external monitor. This should reduce the CPU usage immediately and no longer pressure your system. We know it is not the most suitable solution for users, but try it for the experiment purpose. If WindowServer changes its behavior after running this step, then you have detected the culprit. You may also try to disable “separate Spaces” for monitors in settings. Although many users found it useless, we recommend you give it a try nonetheless.

To disable Separate Spaces:

  1. Open System Preferences as we did in the previous methods.
  2. Click on Mission Control and disable feature called Displays have separate Spaces.
  3. To let this change come to work, you have to reboot your Mac. Do it and check if there is a difference.

disable separate spaces

7. Delete recently installed programs from Mac

There are programs that may be unwanted and lead to excessively high consumption of resources. If you remember installing a new program from App Store or third-party resources right before the problem with WindowServer, try to delete it and see the difference. Sometimes users may be infected with adware or browser hijackers, which change browser settings and eat a multitude of resources to sustain their suspicious functions. You can use manual instructions or use a specially-educated utility that will take this task onto its own shoulders.

Many unwanted programs can launch at the startup and work in the background causing various conflicts. Thus, if it is a sticky and unwanted program, you should do the following. Otherwise, use basic deleting by dragging a program from Applications and emptying the Trash.

  1. Open System Preferences, choose Users & Groups.
  2. Choose your account (set up as Current User).
  3. Click Login Items tab.
  4. Find an entry similar to the name of a stubborn program. Select it, and click the “-“ (minus) button to remove it.

Note: An unwanted prgoram is less likely to quit simply by closing the window. It is advised to use Force Quit that will end the whole process.

  1. Press 3 buttons at the same time: Option, Command, and Esc (Escape). This is similar to Control-Alt-Delete on a Windows PC.
  2. Choose the name of an unwanted app in the list.
  3. Click Force Quit button.

Remove software from Applications:

  1. In the Finder sidebar, click Applications.
  2. A program you looking to delete might have an Uninstaller. If you see an icon named “Uninstaller” or similar, double-click it and follow the onscreen instructions.
  3. Otherwise, drag the desired program from the Applications folder to the Trash (located at the end of the Dock).
  4. Then choose Finder > Empty Trash.

Remove malicious or stubborn software from MacOS:

malwarebytes for mac

To save your time and effort on deleting programs and finding malware, it is better to use advanced system-optimization utilities like Malwarebytes for Mac. Be it a virus or unwanted program, a group of high-skilled developers ensured they will be detected and removed in a couple of seconds. It allows fast and traceless uninstallation of various software that strains your system. Malwarebytes for Mac is a great tool that will keep your Mac clean, optimized, and protected against various threats in the future. If you are afraid to leave some traces while approaching removal yourself, download Malwarebytes for Mac and make your life easier using the button below.

Download Malwarebytes for Mac


Getting in trouble with WindowServer and other related pieces may hurt your mood and user experience while using the system. Nobody likes when it happens, especially on highly-priced Macintosh devices you pay for. We hope we managed to provide an easy and effective guide that finally reduced CPU usage and made system performance better. Feel free to leave your comments below and share some WindowServer details from your experience.

Previous articleHow to remove OriginType (Mac)
Next articleHow to remove Giuliano Ransomware and decrypt .Giuliano files
James Kramer
Hello, I'm James. My website Bugsfighter.com, a culmination of a decade's journey in the realms of computer troubleshooting, software testing, and development. My mission here is to offer you comprehensive, yet user-friendly guides across a spectrum of topics in this niche. Should you encounter any challenges with the software or the methodologies I endorse, please know that I am readily accessible for assistance. For any inquiries or further communication, feel free to reach out through the 'Contacts' page. Your journey towards seamless computing starts here