"COM.APPLE.PHOTOMODEL" Unbelievable.
How can I stop that process from consuming all of my RAM and hanging my new iMac? Thanks!
iMac 21.5", macOS 10.14
The only way to stop it is to shut the Photos app down.
Personally, I would never even consider using this app. You original photos get trapped in its database and you have to export everything to get them back out.
There is a way to get at the originals with the contextual choice of Show Referenced File in Finder, but that only works if you are completely managing the assets manually, which is not how most people use Photos. You can also dig around in the database via the Finder, but it clearly is not setup to be accessed that way.
If you have a lot of photos to manage, use an app that's intended for it; a digital asset manager (they handle more than just photos). Nothing you put in the asset manager becomes part of it. Your images and other documents stay wherever you have them. Main drive, external drive, etc. The only thing they save is a thumbnail of each image so you can peruse your database even if the drive the originals are on aren't mounted.
I was using iView Media Pro, which changed hands through Microsoft as Expression Media, and eventually Media Pro at Phase One. Rather than updating the app to 64 bit (which they had years of time to do), they simply dropped it and expected you to purchase a very expensive alternative app of theirs that wasn't really even meant for this type of thing.
After searching around and testing at least six different similar apps, I found NeoFinder. Mostly identical to Media Pro and not expensive. Only $40 for a single user license. You can download and test it for xxx number of days with a small set of images.