There seems to be some sort of performance issue with rescan if you have several playlists in the playlist directory.

I have tree playlists with 200 tracks in each and totaly 2780 tracks in the database and performs a full rescan. The rescan without playlists takes less than a minute with tree playlists it takes several minutes. I also tried it with 9 playlists and then I gave up waiting after about 10 minutes of rescanning. It seems to be working because it uses about 80% CPU and if I look in the genre_track table rows are slowly added to it.

There is also a simliar problem when performing a playlist rescan with a single playlist in the playlist directory because then the full rescan works pretty fast, but when I try to perform a playlist rescan it seems to take forever.

I am using the mysql database if that matters.

Rescanning with playlists works a lot faster with 6.2.1 and 6.2.2 but in these versions entries are incorrectly removed from the genre_track table as reported in separate problem reports, which makes them unusable with several playlists.