Arch Linux

hotvic

Member

Registered: 2013-02-11

Posts: 109

Mount 100% Full btrfs partition

I'm trying to mount as rw a btrfs partition which is 100% full.
I'd converted from ext4 to btrfs but the partition had only 1.5GB free. after the conversion the "ext2_saved" subvolume has been fulling the partition and when I try to mount I get "No space left" message.

WorMzy

Forum Moderator

From: Scotland

Registered: 2010-06-16

Posts: 11,907

Website

Re: Mount 100% Full btrfs partition

Could you post the dmesg entries that are generated upon a failed mount? Can you mount with -o ro?

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Sakura:-
Mobo: MSI MAG X570S TORPEDO MAX // Processor: AMD Ryzen 9 5950X @4.9GHz // GFX: AMD Radeon RX 5700 XT // RAM: 32GB (4x 8GB) Corsair DDR4 (@ 3000MHz) // Storage: 1x 3TB HDD, 6x 1TB SSD, 2x 120GB SSD, 1x 275GB M2 SSD

Making lemonade from lemons since 2015.

hotvic

Member

Registered: 2013-02-11

Posts: 109

Re: Mount 100% Full btrfs partition

WorMzy, I've to boot a live to get the dmesg messages. And yes, I can mount as read-only.

Spider.007

Member

Registered: 2004-06-20

Posts: 1,175

Re: Mount 100% Full btrfs partition

The ext2-saved actually shouldn't take up any significant space; did you try rolling back the conversion? Also; it'd be nice if you get `btrfs fi df` output from the drive to determine if it's data or metadata that's full (but that only seems to work on mounted devices). Did the conversion complete succesfully btw?

WorMzy

Forum Moderator

From: Scotland

Registered: 2010-06-16

Posts: 11,907

Website

Re: Mount 100% Full btrfs partition

WorMzy, I've to boot a live to get the dmesg messages. And yes, I can mount as read-only.

That's fine, but please boot one with a recent kernel (the latest Arch live ISO should be fine). Redirect the dmesg output to a file and use a pastebin client to upload it, then post the link here.

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Sakura:-
Mobo: MSI MAG X570S TORPEDO MAX // Processor: AMD Ryzen 9 5950X @4.9GHz // GFX: AMD Radeon RX 5700 XT // RAM: 32GB (4x 8GB) Corsair DDR4 (@ 3000MHz) // Storage: 1x 3TB HDD, 6x 1TB SSD, 2x 120GB SSD, 1x 275GB M2 SSD

Making lemonade from lemons since 2015.

hotvic

Member

Registered: 2013-02-11

Posts: 109

Re: Mount 100% Full btrfs partition

The partition was damaged and probably unrecoverable, so lost all data, doing a full new installtion.

ratcheer

Member

Registered: 2011-10-09

Posts: 912

Re: Mount 100% Full btrfs partition

Sorry I'm too late, but the same thing happened to me. Somehow, I managed to mount it rw well enough (using advice from the btrfs irc channel) to delete the subvolume containing the backed up ext4 partition. Then, I could boot, normally. Next, I defragmented all data and directories. Since then, everything has worked well and the same system is currently my main Arch system; it has been running for months.

Tim

hotvic

Member

Registered: 2013-02-11

Posts: 109

Re: Mount 100% Full btrfs partition

ratcheer, that's the problem, I don't figured out how to delete the subvolume w/o mount it as rw first.

Any way, Thanks!

Spider.007

Member

Registered: 2004-06-20

Posts: 1,175

Re: Mount 100% Full btrfs partition

btrfs-convert has a rollback option (-r)