Re: [PATCH 0/4] btrfs: sysfs and unsupported temp-fsid features for clones

["Guilherme G. Piccoli" <gpiccoli@igalia.com>]

On 10/10/2023 01:59, David Sterba wrote:
> On Mon, Oct 09, 2023 at 01:37:22PM +0530, Anand Jain wrote:
>>>> Can Guilherme send an RFC patch for feedback from others and
>>>> copy suggested-by. Because, I haven't found a compelling reason
>>>> for the restriction, except to improve the user experience.
>>
>> My comments about the superblock flag are above.
>>
>> User experiences are subjective, so we need others to comment;
>> an RFC will help.
> 
> A few things changed, the incompat bit was supposed to prevent
> accidentally duplicated fsids but with your recent changes this is safe.
> This would need to let Guilherme check if the A/B use case still works
> but this seems to be so as I'm reading the changelog.
> 
> In a controlled environment the incompat bit will not bring much value
> other than yet another sanity check preventing some user error, but
> related only to the multiple devices.

Hi David and Anand, I've manage to test misc-next of today, that
includes both this patchset as well as the "support cloned-device mount
capability​" one.

It seems to be working fine for our use case, though I'll test a bit
more on Deck. I was able to mount the same filesystem (spread in 2 nvme
devices) at the same time, in any order...the second one always get the
temp-fsid. Tested also re-mounting the devices on other locations, and
it seems all consistent, with no error observed.

I also question the value of the incompat flag, not seeing much use for
that..looping Qu Wenruo as they first suggested this flag-based
approach, in case there is some more feedback...

Anyway, thanks for your improved approach Anand and to David: is it
expected to land on 6.7?
Cheers,


Guilherme