Files can grow as many as 17GB of leftovers because playlists are at least 500MB big. It became a problem after at least 3 months of usage, which included early test days of the feature, but my customer is really averse to technology (a very good tester), and there is no day he doesn't mess up something (must admit that sometimes the blame is on me tough)...
On my production server, which is very narrow in resources, the proc takes around 1,5 seconds to return from /ds/shell. I have around 1000 files and it returns around 250 orphans.
