In /var/log/syslog, I get a LOT of messages like:

Jun  7 21:14:19 mint ureadahead[844]: ureadahead:/etc/lvm/lvm.conf: Error retrieving chunk extents: Operation not supported

With the filename - now /etc/lvm/lvm.conf - different every line but often referring to programs I just opened.

There are 5,208 lines like this in the log, printed in just 2 seconds time.