On 2019-02-12 2:22 a.m., Qu Wenruo wrote:

>> Does this mean you would rely on scrub/CSUM to repair the missing data
>> if device is restored?
> 
> Yes, just as btrfs usually does.
> 

I don't really understand the implications of the problems with mounting
fs when single/dup data chunk are allocated on raid1, but I would think
that would actually be a preferable situation than filling a drive with
'data' we know is completely bogus... converting single/dup data to raid
should be much faster than tripping on CSUM errors, and less prone to
missed errors?