Command to trim an SSD:sudo fstrim --all (or sudo fstrim -a)Returns 0 (success), 32 (all failed) or 64 (some failed)Commands to enable automatic trim:A systemd .timer that will automatically run `fstrim -a` every week can be enabled in Debian with these commands:sudo apt install util-linuxsudo cp /usr/share/doc/util-linux/examples/fstrim.{service,timer} /etc/systemd/systemsudo systemctl enable fstrim.timersudo systemctl start fstrim.timerCheck the status of the .timer with:sudo systemctl list-timersStop the .timer from running automatically with:sudo systemctl disable fstrim.timerRead `man systemctl` & `man systemd.timer` for more on this.