WindowServer High CPU usage while connected to external monitor - Big Sur

Hello!

The problem described here in the thread is still not solved even with the latest Big Sur update to 11.5.1!

https://discussions.apple.com/thread/252089464

I have a Macbook Air M1 with a Samsung C32JG52 QHD monitor which I use as an external monitor! After a few hours of operation, the CPU load of the Windows server process sometimes increases to 100%, no matter how many windows I have open - the mouse jerks, videos I play in the browser via Youtube also, etc... even if I then close some windows, the CPU load of the process always jumps back to high values! For that the Macbook has such a power is the behavior shown as soon as you connect an external monitor but to say the least a disaster, a productive work is not possible!

I've had a bit of a speedup by disabling "Displays have seperate spaces" in the System Preferences, but it's still happening.

Is someone from Apple Support reading along here and is this problem, which apparently also affects various others under Big Sur, finally being addressed?

Posted on Jul 28, 2021 11:55 PM

20 replies

Aug 26, 2021 5:27 AM in response to MikeDeltaHH

Just so it’s clear: I do not work for Apple. I am a user like you. This os a user forum.

Good luck. I am out.

varta1

Level 1

4 points

Aug 2, 2021 12:56 AM in response to MikeDeltaHH

It's definitely not an isolated problem, I am running into the same issues on MBP 2020 (Intel) with the latest macOS ever since upgrading to Big Sur. Having 2 external monitors connected along with using the laptop's built-in screen makes the laptop unusable anytime I start a video call (Google Meet), as the CPU spikes to 95-100% usage and the system becomes unusable.

C'mon Apple, allow me to work on a google document while being on a video call on your $2000 laptop, smh.

Aug 4, 2021 11:08 AM in response to varta1

I've recently experienced similar issues since upgrading to Big Sur. My experience is when WindowServer utilization is high, I cannot maintain my camera video in Teams and the video of my attendees flickers. The mouse barely moves or responds in Teams. I don't have this experience when I'm disconnected from my monitors.

Oct 18, 2021 4:18 PM in response to MikeDeltaHH

This has been a frustrating problem. We have a few machines that are affected. I think maybe there are multiple things that must be true before the bug hits. External monitor and… something else installed? I’ve done everything I can think of and just can’t figure it out.

This is on a 15” 2015 with 16 GB of RAM. I used the machine with zero issues for years, then handed it down. Now it happens constantly. I’ve rebuilt the software side from the ground up with no better results.

The only other thing to check is your fans. On one machine we did see that. Machine wasn’t being cooled, so it throttled as more work was thrown at it.

MikeDeltaHH Author

Level 1

10 points

Aug 4, 2021 11:14 AM in response to Luis Sequeira1

It seems i´m not the only one with this problem - the source seems Big Sur with external Monitor... ist there any chance to fix this problem?

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WindowServer High CPU usage while connected to external monitor - Big Sur