Photos slow to respond to various commands

Hi

Not totally clear - copied to library on this internal HD - just to confirm the library is on your system drive, correct?

Increasing instability suggests a damaged library:

Have you ever used any speed up or clean up apps, or duplicate removal apps? Many of these are not "photos library aware" and can cause damage. Libraries can also be damaged by being stored on an incompatible volume, or on a networked location, or a different cloud service (such as dropbox). (again, where is your library stored?). Or just simple drive failure or faults on parts of the drive.

Before trying anything else though, it might be worth trying a restart in safe mode which can sometimes fix random glitchyness.

Start up your Mac in safe mode – Apple Support (UK)

If that doesn't help, then the easiest way to eliminate library damage as the problem (if everthing you need is in iCloud) will be to sync iCloud with a new empty library. If you want to try that, here's how:

1 - Create a new EMPTY library in your pictures folder. (Hold down the option key while starting photos, and click "create new". Name it something that is easy to recognise).

2 - Open the new empty library in photos. (it should open after you click "create new" but if not, use the option key start again, and select the new library from the list.)

3 - In photos preferences set it to the system library (click the circled button)

4 - In photos preferences iCloud - turn iCloud on with download originals.

5 - Wait - for photos to download all your images from iCloud into your freshly minted library. It may take some time - possibly days. Leave the mac on with photos open and sleep disabled while it is doing it.

new-to-apple wrote:

Can I uninstall the Photos program and reinstall, or would this do further damage or nothing at all? Any help will be appreciated.

Photos is a part of the system and can only be reinstalled by reinstalling the system. This would only be useful, if the problem with Photos is system wide and happens also when working from a different user account. You could sign into the guest user account and create there a small Photos Library for testing.

If you are having similar problems in a different user account with a different Photos Library, check your hardware. You may simply be running out of storage on your system drive, or the mac may not have enough memory installed, or the memory is faulty, or the system drive is having problems.

System wide trouble could also be caused by incompatible third party software being installed. This can be checked by running the mac in safe boot mode.

if the erratic behavior only occurs in your user account and only in your current Photos Library, you may want to check, if there are incompatible media files in your Photos Library. After the upgrade to macOS 10.15 Catalina, some older 8mage formats and video formats can no longer be processed by Photos. Leaving files 8n a legacy format in the library can cause Photos to hang or even crash. Remove all files that are appearing in an album “unable to upload”. Keep only photos and videos in your library that are in format that you have tested and know it is still working.

For clarity.

iCloud ALWAYS stores full resolution images, so that it can sync them to other devices if that is what you do - but also to give a measure of data security (though it should NOT be relied upon as your only backup).

You have the option on any device to "optimise device storage". What that does is only keep small previews on your mac, to take up less disk space. Photos will then download the full resolution images from iCloud when needed, eg for editing, printing or export.

So if you sync to a new library, then you will have the full quality images in that library.

Yes - work with the new library a while. When you are confident it is working AND you have everything in it you need, then it is fine to delete the old library.

Yes, the new library will be totally separate. Be aware though that it will only have in it what was in iCloud. If there is a risk that there were photos in the old library that are not in iCloud, it might be worth taking a copy of the old library to an external drive before deleting it.

Cool - glad it is looking all OK.