Error-Fixing Btrfs FSCK Tool Is Imminent

[mikhmv]

btrfs is unstable and fsck is not working

Current implementation of btrfs completely unstable. It even does not need power outage to make system unrecoverable.
Yesterday we setup wget downloading from 10 different sources. in the result system gave kernel panic. We can not mount it now at all and current fsck gave following message.

~$ sudo btrfsck /dev/vdc
[sudo] password for biouml:
parent transid verify failed on 20971520 wanted 1347 found 3121
parent transid verify failed on 20971520 wanted 1347 found 3121
parent transid verify failed on 20971520 wanted 1347 found 3121
parent transid verify failed on 20971520 wanted 1347 found 3121
Ignoring transid failure
parent transid verify failed on 29470720 wanted 1357 found 3231
parent transid verify failed on 29470720 wanted 1357 found 3231
parent transid verify failed on 29470720 wanted 1357 found 3231
parent transid verify failed on 29470720 wanted 1357 found 3231
Ignoring transid failure
parent transid verify failed on 29470720 wanted 1357 found 3231
Ignoring transid failure
parent transid verify failed on 29487104 wanted 1357 found 3235
parent transid verify failed on 29487104 wanted 1357 found 3235
parent transid verify failed on 29487104 wanted 1357 found 3235
parent transid verify failed on 29487104 wanted 1357 found 3235
Ignoring transid failure
leaf 29487104 items 1 free space 3454 generation 3235 owner 7
fs uuid c5ce4702-2dbf-4b57-8067-bd6129fc124b
chunk uuid 0ffa84fe-33a3-4b8e-95a4-de5f93e88163
item 0 key (EXTENT_CSUM EXTENT_CSUM 64343257088) itemoff 3479 itemsize 516
extent csum item
failed to find block number 150802432

With ext4 I have never had problems during regular multithreaded IO, but btrfs cannot handle even this.

[Markore]

ZFS already does not need offline fsck for many years...

ZFS has all that Btrfs yet needs to be developed and it is in use for years.

Since recently, you can also run Linux on ZFS using ZFSOnLinux implementation, besides Zfs-Fuse , Solaris, Openindiana (Illumos) , SmartOS , Nexenta and FreeBSD.

Why would I wait for fsck?
ZFS has disk scrub and it can do disk check while server is in production.

I think that even on desktop I am angry to fsck stopping me to log into my machine every once in a while, when Ubuntu wants do to pre-boot fsck of my ext4 system disk... While I am waiting and asking myself, when I will install my Ubuntu on ZFS and avoid this..

I suppose since Btrfs is still in heavy development, fsck is needed for some serious crashes during development but
I was thinking Btfrs would be more like ZFS in a manner of robustness.

Oracle also has ZFS in it's portfolio, all it needs it to dual-license ZFS to GPL, besides CDDL and implement it isn Linux kernel.
Oh, sorry, ZFS is already done ported to Linux, with ZfsOnLinux via Solaris porting layer and ZFS tend to control "everything", so you do not need Linux facilities to manage your disks with all Raid Levels, actuallly..

[Tiger_Coder]

Error in btrfs

I have errors in my btrfs home partition. And some times the when some application is trying to read big files from my home directory, it took much much more time then from even ntfs/fat drives. Don't know if that for the errors. Anyway a fsck with error correcting capabilities is required.

[sirdilznik]

What's the big deal about fsck? I've had a power loss corrupt ext4 beyond fsck repair, never had a problem with btrfs.

The big deal is that fsck is a contingency plan. With a fsck tool (capable of repairing issues not just reporting them) you at least have a chance of fixing things if something gets corrupted. Not having a fsck tool is like driving around in your car without a spare tire, a jack, or a cell phone. Everything is fine as long as you don't get a flat.

[pdffs]

Likewise, Ubuntu can not use it be default until either dpkg doesn't fsync (danger!), or btrfs fsync doesn't completely suck (and it still really sucks). This poor fsync performance also makes it unsuitable for a whole lot of workloads.

[RahulSundaram]

How the heck do you know you don't have a problem since there's no fsck for it? Are you psychic?

A fsck that is capable of reporting errors has existed for a long time already. So he doesn't have to be a psychic. Having said that. Fedora is unlikely to default to Btrfs for the next release until all the important issues besides fsck is resolved

https://bugzilla.redhat.com/show_bug.cgi?id=689509

[BlueJayofEvil]

What's the big deal about fsck? I've had a power loss corrupt ext4 beyond fsck repair, never had a problem with btrfs.

I've had the exact opposite in my experience.

[RealNC]

What's the big deal about fsck? I've had a power loss corrupt ext4 beyond fsck repair, never had a problem with btrfs.

How the heck do you know you don't have a problem since there's no fsck for it? Are you psychic?

[smspvdm]

openSUSE

Article fails to mention openSUSE, which had btrfs in 11.4 for some time now (though experimental), and since november 2011 in openSUSE 12.1 it is possible to simply choose it during the install wizard. It even has snapshot capability built into YaST (snapper), so it can revert to the state of the filesystem before your last change for example. Phoronix is unfortunately, again, very Ubuntu biased.

[Hamish Wilson]

What's the big deal about fsck? I've had a power loss corrupt ext4 beyond fsck repair, never had a problem with btrfs.

Huge deal for me, I have had some very nasty corruptions that fsck has fixed up like a charm on ext4.