December Meeting: ZFS on Linux (Aaron Toponce)

Michael Torrie torriem at
Sat Dec 14 12:56:54 MST 2013

On 12/14/2013 10:24 AM, S. Dale Morrey wrote:
> My issue is that boot times are horrendous and I keep finding files that
> have appear to have been "randomly" rolled back to previous versions.  I've
> taken to placing all syncing all of my personal data over to S3 just so I
> don't send someone a 6 month old copy of my resume.  No joke, btrfs ate my
> tax return too :(
> I really don't like this file-system, it's just too silent when it
> detects/corrects random issues.  I would rather it flash a big sign
> "Attention, your hard-drive appears to be horked, would you like to go to
> new egg and order a new one?  In the meantime I'll go ahead and rollback
> files x,y,z to previous versions."

Yes that is a serious problem!   I assume you've reported the bugs?  Are
you using snapshots?  What features did you need that Ext4 couldn't provide?

I'm not using snapshots at all at this point, but I set up btrfs so I
could play with that feature.  Particularly I want to be able to roll
back system updates if something goes wrong, and snapshot my home
directory.  Never quite worked how exactly what I wanted to do, though.
 So I've never had any of the problems you report, at least that I know
of! Silent corruption is always scary!

Back when I first started running ZFS quite a few years back we had
issues with some silent corruption there as well, but the problems went
away with an OS update and we never had any further problems until right
after I left BYU when a bizarre fault (software?) corrupted the entire
12 TB file system beyond recovery.  Both Sun and several data recovery
and file systems experts said what happened was impossible.  Could have
been a hardware fault, could have been software fault.  In any case it
was a bad crash.  Absolutely no data was recovered after significant
effort on the part of some data recovery experts.  They couldn't even
reassemble the RAID array (hardware RAID even), or even tell that it had
ever existed.  That's data security for you!

But I've also lost a lot of data to XFS quirks as well, mostly due to
truncated files. Apparently that's a feature of XFS.

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