Bulk Processing crashed or stuck in loop

I ran bulk processing on about 1,500 images (mostly thumbnails). After 3 hours it has crashed and just keeps lagging, then flashing some files it says it’s converted, then lagging, then flashing the same files again. When I checked the files on the server, it’s only about half done and some of the files it’s saying it’s processed are untouched.

I didn’t see the option to generate on demand this time and obviously should have chosen that instead. So, since I chose mingled I now have a bit of a mess in my uploads. The bulk process is obviously not going to recover so I’m going to officially give up on it in a minute.

Any thoughts or advice for me at this point? I would appreciate any help possible. Best wishes, Tabitha