Compressed Swap file on ubuntu 25.04

README.md

1. Ubuntu 25.04 because LVM VDO (compression) not supported on early versions (I tried 24.04)
2. Installed kernel 6.14
3. apt install lvm2
4. create partition ${your partition number} for swap
5. sudo pvcreate /dev/nvme0n1${your partition}
6. sudo vgcreate vg /dev/nvme0n1${your partition}
7. sudo lvcreate --type vdo -L ${your size}G -V ${your size}G --compression y --deduplication n vg/lv_swap
8. sudo vgchange -ay # activation all created VDO for tests before reboot
9. sudo blkid /dev/vg/lvol0 # remember UUID ${your uuid}
10. sudo nano /etc/fstab # append UUID=${your uuid} none swap sw 0 0 to it
11. sudo systemctl edit --force --full dev-vg-lvol0-swap.service # unit for activation VDO before fstab mounting with content:

### /etc/systemd/system/dev-vg-lvol0-swap.service
[Unit]
Description=Activate LVM volumes before mounting filesystems
DefaultDependencies=no
Before=local-fs-pre.target
After=systemd-udev-settle.service
 
[Service]
Type=oneshot
ExecStart=/usr/sbin/vgchange -ay
 
[Install]
WantedBy=local-fs-pre.target

12. sudo systemctl enable dev-vg-lvol0-swap.service
13. sudo reboot, if you have some problems, just wait timout, it will boot again :)
14. swapon --show # used swaps
15. sudo vdostats --human-readable # compression statistics

Pros: speed up access to data in swap (less data must be loaded from disk) Cons: memory to work VDO and CPU for compression

You can try to use deduplication too...