Photos app Mac stuck on finding duplicates (m2 Mac update 2023)

Hi there,

not so much a question as a description of what worked for me recently. I came across a thread here from 2021 with the following summary which I found quite helpful.

Start quote:

“in my case, for "scanning Photos/Faces/People", it worked to activate the Energy Saver feature "Prevent your Mac from automatically sleeping ...". The screensaver was active, and the screen of my iMac was off over night.

What I did in detail:

• restart the Mac, make sure that no app is running
• check that the Energy Saver feature "Prevent your Mac from automatically sleeping ..." is on
• check with Activity Monitor that there are no "hanging" or stuck processes related to Photos.app. If there are processes that are not changing, quit them. Using the search string "photo" selects the relevant processes. The "circle with X" allows to Stop a selected process.
• open Photos.app - this should result in about 4 to 5 running processes detectable in Activity Monitor (filtered for "photo" in the Process Name).
• once these processes (including photoanalysisd and photolibraryd) have been started, quit Photos.app and leave the Mac alone over night.

For me, this has worked several times (e.g. after using the Repair function of Photos.app) to get about 40.000 photos/pictures scanned.” End quote.

When I got my new m2, I transferred my photos over from a 2016 iMac.

— I did not install any other software

- I disconnected my external monitor

• I was running my photos from an external drive, and made that the default photo library under preferences.
• I repaired the library before doing anything else, even though it was working fine
• otherwise, I followed the above but kept the photos app open.
• it took several days/nights. Each morning I restarted the Mac, opened photos and activity monitor and kept photos open.
• instead of a screen saver I turned the brightness to zero, and turned it back up to check.
• 50,000 photos, 5000 duplicates and counting! Pretty bad,I know.

hopefully this helps anyone with this issue. As tempting as it is to get everything transferred to your new Mac immediately, keeping it free of other background processses and focusing on getting the photos done first worked for me.