Lightroom Classic 10.1.1 appears to be a resource hog. Is there going to be a fix for Apple Big Sur

"This is not a feature enhancement - it is another bug - and Adobe should be releaseing a 10.1.2 patch to fix this - having to wait until February to get 10.2 - which might not fix this issue, is unacceptable when I'm paying so much for a software subscription."

I agree. But Adobe product developers won't see your feedback, since they rarely participate here. They want all product feedback posted to the official feedback forum:

https://feedback.photoshop.com/photoshop_family/categories/photoshop_family_photoshop_lightroom 

They do read everything posted there and often engage with it (but often not).

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I am in agreement with the recommended fix for the current state, provided by John.

I am also user of an earlier iMac 27” 5K system with a standard 2GB GPU card, if you look at LrC Version 10 system requirements “Recomended GPU” it is clear that you should come to the realization that your GPU is not up to the task. It's not possible to upgrade the GPU of your iMac, so if Adobe is unable to make a fix then we no longer have the option toutilize the GPU acceleration feature. My other concern is that while we have upgraded to Big Sur it's likely we will not be able to install the next major upgrade of macOS, our system is on the verge of retirement.

Many people are experiencing problems with LR 10.0, 10.1, and 10.1.1 on all versions of Mac OS. Adobe has acknowledged these issues, and we can hope that 10.2 will fix them.  LR usually releases every two months, and 10.1 came out on 12/8, so we might expect 10.2 the first week of February.  However, 10.1.1 was an unusual "patch" release to fix a cloud-sync problem, so the regular schedule might have shifted (Adobe rarely lets us know ahead of time).

There may be multiple issues going on, so different workarounds have worked for some people:

- Set Preferences > Performance > Use Graphics Processor to Off.

- If you have a custom color profile assigned to your display from a calibrator or running System Preferences > Displays > Color > Calibrate, set the display profile to Color LCD (for a Retina display).

- Roll back to 10.0 (easy):

https://www.lightroomqueen.com/roll-back-update-previous-classic/ 

- Roll back to 9.4 (hard, ask for details if you get this desperate).

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