For the Intel DH67CL/BL motherboard, for example, the motherboard has to be set to "maintenance mode" by a physical jumper to access the settings (see , ).
Follow the tips in Improving performance#Storage devices to maximize the performance of your drives.
However, results vary and particularly earlier SSD generations may also show just the opposite effect.
Also for this reason, some distributions decided against using it (e.g. Note: Enabling this option will "issue discards to a logical volumes's underlying physical volume(s) when the logical volume is no longer using the physical volumes' space (e.g.
Therefore there is no need to worry about too frequent invocations, in an anacron-like fashion.
To query the units activity and status, see journalctl.