Not sure if I properly unterstand they way TRIM on SSD is supposed to work. According to
lspci I’ve got the following device: Samsung Electronics Co Ltd NVMe SSD Controller SM981/PM981. It shows up as nvme0 in /dev. In Ubuntu 19.04 standard configuration, systemd regulary runs
fstrim -Av by systemd
fstrim.service. According to this commands output it only trims /boot/efi and /boot, but not my other filesystems and partitions.
According to documentation I found,
fstrim is only possible if
hdparm -I lists TRIM as a capability of the disk. This just fails with “Inappropriate ioctl for device” and doesn’t list any capabilities at all.
I guess something is broken here?
This happens on Ubuntu 19.04 with latest upgrades applied. The filesystems that are supposed to be trim’ed are on a partition in nvme0, which is setup as LUKS device, which in turn contains an LVM PV with various logical volumes.