Once the swap disk space is exhausted you'll get multiple file access errors each time you attempt to process an image, but the PI Core application should be stable. You can change or add swap directories dynamically and they will be used the next time PI needs to write a new swap file. Of course, you should always try to avoid these situations by providing enough swap space in advance.
Thanks for the confirmation of this. I think what I will do in cases where I am running out of swap is to simply remove the ram disk from the PI swap list. Then the full size on the SSD can be used.
