fstrim

Discard unused blocks on a mounted filesystem. Only supported by flash memory devices such as SSDs and microSD cards. More information: https://manned.org/fstrim.

Trim unused blocks on all mounted partitions that support it:

sudo fstrim --all

Trim unused blocks on a specified partition:

sudo fstrim {{/}}

Display statistics after trimming:

sudo fstrim --verbose {{/}}