What iCloud for windows is doing in the background - it takes 25% cpu capacity by average | and how to solve it

While we don't know what iCloud Photos are doing, we are not able to disable or pause the sync. And signing out of iCloud Windows is not a good idea as I think that will mess up the sync even further or, you need to restart the whole syncing and downloading all over again.

This is what I did, which seems to help somewhat:

1. in Windows Task Manager, right-click on iCloud Photos and click "Go to details"
2. this brings you to the Details tab in Task Manager
3. locate iCLoudPhotos.exe and right-click on it and choose Set Affinity
4. a pop-up appears for you to choose which CPU is allowed to run "iCloudPhotos.exe".
5. uncheck everything and just allow one CPU to run.

I find that that reduces the iCloud Photos CPU usage by half. It dropped from 29% to 14% for me. And when looking at the Performance tab in Task Manager, I can see only one CPU Core chart where the utilization is 100%, where as the other 7 Cores are normal.