Windowserver killing CPU% and performance Etrecheck help

Macbook pro, M3, 18GB, recently updated to Sequoia 15.3.1

It initially had a slow and sticky mouse; now the machine is almost unusable after a couple of hours' use. Windowsever dominates in activity monitor and sits at 30% and runs up to 102%. Once over 80% the machine becomes laggy and then slows to a crawl.

I ran several Etr reports, removed Sophos and Displaylink manager for the external monitor and not used a second screen for two days. Reinstalled Adobe, and deleted anything that looked odd.

The machine runs faster after a restart, but slowly, Windwosever builds up to end up peaking at 100%, and the machine begins to lag and then slow to unusable.

I have attached the last Etrecheck report and provided the very first one if that is helpful.

Etrecheck report 28 Feb

Any help or direction would be amazing.

Posted on Feb 27, 2025 12:56 PM

Top-ranking reply

Fishysydney Author

Level 1

23 points

Posted on Mar 10, 2025 6:25 PM

After lots of support calls and diagnostics it is looking like Grammarly desktop is the cause or at least a major factor.

Two days without Grammarly no issues, two hours with it running almost dead. Logged out and the machine went nuts.

uninstalled and it’s running fine again even without a restart. Will keep you all posted. If you have Grammarly desktop try uninstalling it and see what changes.

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20 replies

melvyn86

Level 1

8 points

Mar 10, 2025 12:41 PM in response to Fishysydney

Me too. Overnight, my M1 went from a sporty machine running all my writing tools to something unusable. MacOS has always been flaky and memory-hogging regarding window management, but this is something else.

Fishysydney Author

Level 1

23 points

Feb 27, 2025 1:31 PM in response to etresoft

I have cleaned up Chrome, removed plugins and history etc. No change.

I have run without any web browser open, No change.

Ahten

Level 1

8 points

Mar 2, 2025 7:30 PM in response to Sendtomenic

Yeah, I got the same issue when using PowerPoint and Excel. But no problem in Word.

So I agreed it may be the update issues. I hope it can be solved asap.

Mar 3, 2025 11:59 PM in response to Ahten

Same problem here. Especially in PowerPoint. Windowserver process is taking more and more CPU time

Ahten

Level 1

8 points

Mar 7, 2025 8:53 PM in response to jzhex

so sad to say , bate version got same issue , just report via the feedback app on the bate version . Hope they can resolve this problem asap

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Windowserver killing CPU% and performance Etrecheck help