I searched these forums and could not find an answer to this question.   I noticed tonight on my SSD cache drive that under /mnt/user/system there is another folder called /libvirt.   I don't know how it got there, if it is supposed to be there and what it is supposed to do if it is supposed to be there.   The folder was created today at 7:37 pm EST.    I'm new to this all and really don't know how it got there.  It contains a file called libvirt.img.