Mac Photos performance issues during editing

Last suggestion is to log into a basic admin user account, Set up users, guests, and groups on Mac,  and see if the problem persists with another test library. This tells us if the problem is limited to your user account or is system wide.

Try these two procedures and see if that helps:

Try resetting the System Management

Controller (but no longer available for the new M1 computers):

https://support.apple.com/en-us/HT201295

Resetting the NVRAM or PRAM

Try resetting the NVRAM or PRAM,

although this issue would be fairly rare:

https://support.apple.com/en-us/HT204063

-- Rich

If the Safe Mode boot doesn't help as a test launch Photos with the Option key held down and create a new, test library.  Import some photos and test to see if the same problem persists. Does it? This tells us if the problem is limited to your current library or is more wide spread.

Then go back to your original library and test again.

Hi

Couple of questions - does this older mac have an SSD?

Is "optimise mac storage" set in preferences? If so, it will need to download the original file from iCloud before it can do anything with it.

Also - if you use iCloud photos - it may well be carrying out a complete new sync, which will be impacting performance. What does the status say at the bottom of the all photos view?

How much free storage do you have on your Mac?

Is your Photos Library syncing with iCloud and using "Optimise Mac Storage"? If yes, then Photos may need to the download the original file from iCloud and toffee storage for the download, before it can start editing. The second editing will be faster, if the downloaded file is still stored locally.

Where is your Photos Library stored? Is it in your Pictures folder or on an external volume?

Try starting the mac in safe mode, and then seeing if you still have the performance issues.

Start normally, and try again.

https://support.apple.com/en-gb/guide/mac-help/mh21245/11.0/mac/11.0