Fwd: Fwd: [COMMAND HANGS] The command 'btrfs subvolume sync -s 2 xyz' can hangs.

[gius db <giusdbg@gmail.com>]

Il giorno lun 7 gen 2019 alle ore 14:31 Qu Wenruo
<quwenruo.btrfs@gmx.com> ha scritto:
]zac[
> >> It's relatively common that extent tree get corrupted before and some
> >> unfortunately operation touching the corrupted extent tree triggered
> >> some user affecting error.
> >
> > Yes, I understand, but the use of filesytem is very specific.
> >
> > This filesystem and others that have had problems with corruption, are
> > used only as backups.
> > So the only operations that are performed are snapshot receive,
> > snapshot create, snapshot delete.
> > After the operations are finished, the filesystem is unmounted.
> >
> > It may just be a coincidence, but the problems of corruptions have
> > occurred very often after a snapshoot delete.
>
> I think this should give us a pretty good clue.
>
> Specific workload, less active usage, and normally no concurrency.
>
> And for the backup usage, you're using relatively new kernel only, right?

Yes, until a few days ago kernel 4.13.9 - 4.17.7 , now kernel 4.19.10 .

> Then this should be something taking into consideration for stress test.
]zac[

I have never been able to reproduce the condition that causes the
problem, currently I wait a few months until the problem decides to
give news of itself.

Gdb