It's not all, but I haven't figured out a rhyme or reason to which ones. It always happens (so far) when I try to save a RAW file from the .CR2 to a JPEG. The files don't show locked in "get info" ... I will log in again, but I don't know how I wouldn't be logged in differently.
also, here is my computer health stats...
I have a Mac laptop running X Yosemite and Photoshop CC. It is under 6 months old, and has 16GB of RAM. Its hard drive has 85GB free out of 250GB. The last time I shut down was just before posting this thread. I have never run a cleanup program.