Hi Uoti, Thanks a lot for your answer. I wasn't aware of the garbage collector. Just after your mail I saw that it is "now" described in the systemd.unit man page, with all answers to my question. :D As I said, unfortunately, we use a fairly outdated version (228) that ships with SLES12 and this version's man page has no info about the garbage collection. Best regards, Paul Paul Nieleck Associate Software Developer, CE EPS BS2000 DS OS4 Fujitsu Mies-van-der-Rohe-Straße 8, 80807 München Germany Email: paul.nieleck@xxxxxxxxxxx Web: https://www.fujitsu.com/emeia/ _______________________________________________ systemd-devel mailing list systemd-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/systemd-devel