On Wed, Apr 7, 2021 at 5:36 PM Andrei Verovski <[email protected]> wrote: > > Hi ! > > I have VM (under oVirt) with single disk thin provision (~600 GB)
I guess you are using block storage? > running NextCloud on Debian 9. > Right now VM HD is almost empty. Unfortunately, it occupies 584 GB (virtual > size = 600 GB) > All partition (except swap and boot) are EXT4 with discard option. You don't need to use discard mount option. fstrim works without it. > in oVirt “enable discard = on”. > > # fstrim -av runs successfully: > /var: 477.6 GiB (512851144704 bytes) trimmed on > /dev/mapper/vg--system-lv4--data > /boot: 853.8 MiB (895229952 bytes) trimmed on /dev/mapper/vg--system-lv2--boot > /: 88.4 GiB (94888611840 bytes) trimmed on /dev/mapper/vg--system-lv3—sys > > When fstrim runs again, it trims zero. I even run “Sparsify” in oVirt. > Unfortunately, actual size is still 584 GB. > > Here is /etc/fstab > /dev/mapper/vg--system-lv3--sys / ext4 > discard,noatime,nodiratime,errors=remount-ro 0 1 > /dev/mapper/vg--system-lv2--boot /boot ext2 defaults 0 > 2 > /dev/mapper/vg--system-lv4--data /var ext4 > discard,noatime,nodiratime 0 2 > /dev/mapper/vg--system-lv1--swap none swap sw 0 > 0 > > When disk was partitioned/formatted, swap and boot were created first and > positioned at the beginning. > > What is wrong here? Is it possible to fix all this ? Discarding data mark the areas in the qcow2 image as zero, but it does not move actual data around (which is very slow). So if the clusters were at the end of the image they remain there, and the actual file size is the same. The only way to reclaim the space is: 1. sparsify disk - must be done *before* copying the disk. 2. move this to another storage domain 3. move disk back to the original storage domain We may have an easier and more efficient way in the future that works with single storage domain, but it will have to copy the entire disk. If the disk is really mostly empty it should be fast. Nir _______________________________________________ Users mailing list -- [email protected] To unsubscribe send an email to [email protected] Privacy Statement: https://www.ovirt.org/privacy-policy.html oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ List Archives: https://lists.ovirt.org/archives/list/[email protected]/message/SSZKKT72AWZS5V5TRPKTNBCRHW4XVQHY/
