Re: Question: how understand the raid profile of a btrfs filesystem

Goffredo Baroncelli
2020-03-22T08:35:02Z

Hi Zygo,

On 3/22/20 12:26 AM, Zygo Blaxell wrote:
> On Sat, Mar 21, 2020 at 10:55:32AM +0100, Goffredo Baroncelli wrote:
>> On 3/21/20 4:29 AM, Zygo Blaxell wrote:
>>> On Fri, Mar 20, 2020 at 06:56:38PM +0100, Goffredo Baroncelli wrote:
>>>> Hi all,
>>>>

[...]

> ...but now you are not running conversion any more, and have multiple
> profiles. It's not really specified what will happen under those
> conditions, nor is it obvious what the correct behavior should be.
>
> The on-disk format does not have a field for "target profile".

Ok, I looked for a confirmation of that.

> Adding one would be a disk format change.

Yes but I think that it would be done in a backward compatible way. I
think to add a field "target profile" in the super-block. The old
kernels will ignore this field, and behave as today. The new ones will
allocates the new chunk according to this field.

To me it seems complicated to

Any thoughts ?

BR
G.Baroncelli

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