I am using Photos on:
- iPad Air 2013 A1474 / iOS 12.4.6
- MacBook Air 2013 / OSx Catalina 10.15.4
- iPhone 7 Plus 2013 A1784 / iOs 13.3.1
- MacBook Pro A1989 / OSx Catalina 10.15.4
All devices are set to synchronise iCloud Photos "Optimise Mac Storage", with the exception of the MacBook Pro, set to "Download originals to this Mac"
On the MacBook Air I have imported thousands photos from older folders on disk. It took a few days to upload to iCloud and sync on other devices.
Once done, for some unknown reasons,
- on MacBook Pro, people and pictures are set and done. No curation
- on iPhone all pictures available, people search doesn't work (empty) results when selecting people
- on iPad it took days to build thumbnails, people search limited to few results
- on MacBook Air, people recognition is not working yet as it is 4 days the computer is "Curating" (tried to reboot twice, still curating): "5.114 photos scanned photos will continue scanning your remaining 24306 photo when you're not using the app and your Mac is connected to power"
I wonder why such a different behavior…
Is face recognition performed in the cloud or locally on each device?
Best Answer
According to Apple: https://support.apple.com/en-us/HT207368
“When you search your photos, all of the face recognition and scene and object detection are done completely on your device”
Now, about your issue, here are some things you should know and can try that might answer your question.
I just tried this with my iPad and iPhone, and both devices have empty People albums until I add my name to my face manually and then all photos where I appear are sorted.
Edit: Faces that appear constantly throughout your library might appear in the People album on their own, but you should still add whomever you desire manually for best results.