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zidarsk8

Member

Registered: 2011-12-06

Posts: 97

[solved] Btrfs compress mount option not working

If I mount a subvolume with

mount -o subvol=usr,compress=lzo,noatime /dev/sda4 /mnt/usr

and then run the mount command, I get

...
/dev/sda4 on /mnt/usr type btrfs (rw,noatime,space_cache)
...

and there is no compression there. Even with genfstab, there is only the subvolume option.

# /dev/sda4 LABEL=root
UUID=0fd2b9e6-68ab-42d0-80b2-d0072215a71e	/usr      	btrfs     	rw,noatime,space_cache,subvol=usr	0 0

How can I see if compression really works (something like 'zpool get all' command in zfs), and how can I enable it with the mount command. generating fstab and rebooting is no good, since if you're trying to install on a compressed btrfs volume, you need to mount it before runningi pacstrap.

Thank you for any help and hints you might have. And keep in mind I don't know much about btrfs, I'm just learnig as I go along.

Last edited by zidarsk8 (2014-06-13 12:49:33)

zidarsk8

Member

Registered: 2011-12-06

Posts: 97

Re: [solved] Btrfs compress mount option not working

I made a script to run in virtualbox, to test btrfs, and the problem seems to be me:

I copy pasted the compress option from this btrfs wiki page, because i'm always afraid of typos. It seems that was wrong, since if I manually retyped the command, it all seems to work nomall.

ps: I don't know how to delete this thread, so I'm just gonna mark it as solved. Sorry for spamming the forum like this.