I have a 256 GB (~230 GiB) disk, but I found there’s only about 177 GiB of disk space is actually usable after a Qubes installation.
[niconiconi@dom0 ~]$ sudo pvs
PV VG Fmt Attr PSize PFree
/dev/mapper/luks-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx qubes_dom0 lvm2 a-- 231.39g 46.28g
[niconiconi@dom0 ~]$ sudo vgs
VG #PV #LV #SN Attr VSize VFree
qubes_dom0 1 89 0 wz--n- 231.39g 46.28g
[niconiconi@dom0 ~]$ sudo lvs
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
pool00 qubes_dom0 twi-aotz-- 177.06g 74.12 52.19
root qubes_dom0 Vwi-aotz-- 177.06g pool00 9.25
swap qubes_dom0 -wi-ao---- 7.69g
[...]
Where does the ~50 GB disk space go? Is it used internally by Qubes, if so, how? I tried to search for a technical explanation but couldn’t any information. The closest thing I got was a GItHub Issue, asking the same question
Do you know why the size of the pool is less than the size of the available space on the drive? The test drive I installed QubesOS 4.0 (default install, no custom storage settings) on is 118 GB, qubes_dom0-swap is 7.6 GB, but the pool is only 94GB - are ~15 GBs missing?
A user speculates that…
I think the 15-16GB free might be space left to allow resizing the metadata LV for the thin pool, which is limited to 16GB size (just a guess though). […] I think the installer just creates a swap partition with size half of the current RAM
Yes, I do have a large swap, but it still can’t explain the rest 40 GiB of missing space. Does LVM needs that much metadata for thin provisioning? Could anyone give me links to some documentation on how the storage works under the hood in QubesOS?