Comment # 6 on bug 1017461 from Richard Weinberger

(In reply to Ronan Chagas from comment #4)
> Hi guys!
> 
> Yes, this is a **very** serious problem. I have already reported that my
> system is unresponsive every time btrfs maintenance starts, and I am using
> Tumbleweed. I posted to the mailing list, but received just one answer:
> 
> https://lists.opensuse.org/opensuse-factory/2016-09/msg00130.html
> 
> Indeed, when I **disabled** quotas here, then the freeze stopped. Thanks for
> that workaround! Actually, a btrfs developer (Chris Murphy) has already
> warned that the quota feature is not stable in btrfs and must not be used by
> default on production systems:
> 
> https://lists.opensuse.org/opensuse-factory/2016-09/msg00032.html
> 
> However, some openSUSE developers contradicted Chris, specially Richard
> Brown:
> 
> https://lists.opensuse.org/opensuse-factory/2016-09/msg00085.html
> 
> Hence, nobody took the advice and quotas were enabled by default in Leap
> 42.2.
> 
> Maybe now with this bug, which I can confirm that is happening in **all** my
> machines with quotas enabled (HP Workstation, Dell laptop, and a Macbook),
> this problem can be revisited. Furthermore, disabling quota fixes it also in
> all my machines.

Hmmm, I fear quotas are enabled because of snapper(8). It seems to use them
for some clean-up policies.