answered
2017-09-21 00:42:36 +0200
How to check if this is the problem
Run ps aux | grep -v grep | grep tracker-extract
from a terminal. On a working system, you should see a line of text that shows that the process /usr/libexec/tracker-extract
is running. If you see nothing instead, it is a confirmation that this is the problem that affects you.
Cause
tracker-extract
, the process responsible for extracting metadata from audio and image files, choked on some malformed files and crashed.
Solution
Run manually /usr/libexec/tracker-extract -v 3
. This runs the metadata extractor with debugging output enabled. From there you can catch errors: in my case, a few files were causing a "Floating Point Exception". When I removed these files and restarted the phone, the indexing worked again.