btrfs compression not configured.

[JeremiahCheatham]

btrfs compression is not setup even when chosen. Its not compressed and not added to fstab.

[Torxed]

i'll investigate!

[ei-ke]

I can confirm the missing compression though explicitly enabled on my cureent install.

[guerra08]

Same thing happened on a fresh install.

[Vixeliz]

Same thing here, anyone who wants to enable it after the fact see here 'https://wiki.archlinux.org/title/btrfs#Compression' you can compress existing files and add compress=zstd to your fstab.

[kassindornelles]

i can confirm, even selecting to enable compression in btrfs running archinstall with --advanced it does nothing.

[Torxed]

I'll see if I can get that sorted before tagging the full release of v2.5.1. Hopefully it's just a small issue and nothing that requires too much tinkering.

[legymhueck]

I can confirm that, too. Previously, the compression was zstd:3, now it's gone in fstab. If possible, give the user the freedom to choose the compression level. I found that on older systems, zsdt:1 appeared snappier than zstd:3.

[xerxeslins]

I would like to confirm the same error here.

Yesterday I selected the option to install (btrfs with compression), and at the end of the installation there was nothing in fstab related to compression.

I manually added:

compress-force=zstd:15

to fstab.

But I was wondering if it would still be necessary to run:

btrfs filesystem defragment -r -v -czstd /

Anyway, the installer didn't do this automatically.

Thanks.

[Torxed]

But I was wondering if it would still be necessary to run: btrfs filesystem defragment -r -v -czstd /

This is a good workaround in case people noticed the fstab issue late into their usage. But we'll make sure it gets in there.

---

Edit, for my own sanity when I debug this: We run the following mount command when we mount with compression during installation.

# mount /dev/mapper/ainstsda2 /mnt/archinstall/var/log -o compress,subvol=@log

Which doesn't show up on mount information

/dev/mapper/ainstsda2 on /mnt/archinstall/var/log type btrfs (rw,realtime,space_cache=v2,subvolid=258,subvol=/@log)

From the Btrfs wiki there's a small note:

During configuration, add compress=zstd to the mount options of the root file system in fstab.

I'll try to solve this by plugging in a genfstab plugin from the btrfs setup stages, so that it inserts itself enabling less code.

[Torxed]

This should now be fixed in master. I'll try to test this thurrowly within the couple of days and release a new version. Thank you all for bringing this to our attention : )

[phocks]

This may be an issue here again. Just tried a fresh archinstall with btrfs and compression setting enabled, but no compression set in the fstab on system boot.