SSD

Trim

To discard unused blocks on a mounted file system

# fstrim -v /
# fstrim -v /var
# fstrim -v /home

Issues of Samsung SSDs

203475: Samsung 860 EVO queued TRIM issues - Kernel.org Bugzilla

201693: Samsung 860 EVO NCQ Issue with AMD SATA Controller - Kernel.org Bugzilla

Recommended the following "fix":

# echo 1 > /sys/block/sda/device/queue_depth

# echo max_performance > /sys/class/scsi_host/host*/link_power_management_policy