Photos on Mac slow and crashing.

[Loaded] uk.co.markallan.clamxav.freshclam.plist (App Store - installed 2015-11-28)

There is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus or security apps on your Mac.  This user tip describes what you need to know and do to protect your Mac: Effective defenses against malware and other threats - Apple Community   

Uninstall ClamX according to the developer's instructions and rerun Etrecheck to verify that the files have been removed. You can check to see if you've removed all of the supporting files by downloading and running Find Any File to search for any files with the application's name  and the developer's name in the file name.  For ClamX you'd do the following search(es): 

1 - Name contains clamx

Any files that are found can be dragged from the search results window to the Desktop or Trash bin in the Dock for deletion.

FAF can search areas that Spotlight can't like invisible folders, system folders and packages.  

Additionally, log into another vanilla admin user account, Set up users, guests, and groups on Mac,  run for a while and see if the problem persists. (This tells us if the problem is limited to your user account or is system wide).

Then boot into Safe Mode (How to use safe mode on your Mac - Apple Support) by booting with the Shift key held down, reboot normally and test again.

NOTE: Safe Mode boot can take up to 10 minutes as it's doing the following; 

• Verifies your startup disk and attempts to repair directory issues, if needed

• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)

• Prevents Startup Items and Login Items from opening automatically

• Disables user-installed fonts 

• Deletes font caches, kernel cache, and other system cache files

If the local library is still syncing to iCloud you may have to wait for a while to let it finish. Keep the Mac on at night. Photos doesn't have to be open.

It may not the the culprit in this situation but it's a totally unnecessary app to have on a Mac as there are no known viruses for Macs. If you want to check for adware or malware occasionally download and run the free version of Malwarebytes. It was developed by a long time contributor to these forums and a highly respected member of the computer security community. 

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