自去年二月以来，我一直在运行 Ubuntu 20.04 桌面。
\n今天我发布sudo systemctl enable fstrim.service并收到了这样的消息：
The unit files have no installation config (WantedBy=, RequiredBy=, Also=,\nAlias= settings in the [Install] section, and DefaultInstance= for template\nunits). This means they are not meant to be enabled using systemctl.\n \n\nPossible reasons for having this kind of units are:\n\xe2\x80\xa2 A unit may be statically enabled by being symlinked from another unit's\n .wants/ or .requires/ directory.\n\xe2\x80\xa2 A unit's purpose may be to act as a helper for some other …