Re: Is NFSv4.2's clone_blksize per-file or per-file-system?

On Fri, Aug 8, 2025 at 8:38=E2=80=AFPM Trond Myklebust <[email protected]> =
wrote:
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>
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> On Fri, Aug 8, 2025 at 9:47=E2=80=AFPM Rick Macklem <[email protected]=
om> wrote:
>>
>> Hi,
>>
>> I'm looking at RFC7862 and I cannot find where it
>> states if the clone_blksize attribute is per-file or
>> per-file-system.
>>
>> If it is not in the RFC, which do others think it is?
>> (Or maybe, if you have implemented CLONE,
>> which does your implementation assume?)
>>
>> In case you are wondering why I am asking,
>> it turns out that files in a ZFS volume can have
>> different block sizes. (It can be changed after the
>> file system is created.)
>>
>> Thanks, rick
>>
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> Yes, but since ZFS only supports filesystem level snapshots, and not actu=
al file cloning, does that matter to anything?
ZFS now has a feature it calls block cloning, which does clone file ranges.
(It was only added recently. I do not know if the Linux port uses it yet?)

rick

>
> Cheers
>   Trond