Re: Is 14.0 to released based on 0 for sysctl vfs.zfs.bclone_enabled ?

On 4 Nov 2023, at 4:01, Ronald Klop wrote:

> On 11/4/23 02:39, Mark Millard wrote:
>> It looks to me like releng/14.0 (as of 14.0-RC4) still has:
>>
>> int zfs_bclone_enabled;
>> SYSCTL_INT(_vfs_zfs, OID_AUTO, bclone_enabled, CTLFLAG_RWTUN,
>> &zfs_bclone_enabled, 0, "Enable block cloning");
>>
>> leaving block cloning effectively disabled by default, no
>> matter what the pool has enabled.
>>
>> https://www.freebsd.org/releases/14.0R/relnotes/ also reports:
>>
>> QUOTE
>> OpenZFS has been upgraded to version 2.2. New features include:
>>      •
>> block cloning, which allows shallow copies of blocks in file copies. This is optional, and disabled by default; it can be enabled with sysctl vfs.zfs.bclone_enabled=1.
>> END QUOTE
>>
>
>
> I think this answers your question in the subject.

I think so too (and I wrote that text).

>> Just curiousity on my part about the default completeness of
>> openzfs-2.2 support, not an objection either way.
>>
>
>
> I haven't seen new issues with block cloning in the last few weeks mentioned on the mailing lists. All known issues are fixed AFAIK.
> But I can imagine that the risk+effect ratio of data corruption is seen as a bit too high for a 14.0 release for this particular feature. That does not diminish the rest of the completeness of openzfs-2.2.
>
> NB: I'm not involved in developing openzfs or the decision making in the release. Just repeating what I read on the lists.

There was another block cloning fix in 14.0-RC4; see the commit log.
Maybe there will be no more issues, but it seems that corner cases were
still being found recently.

		Mike
>
> Regards,
> Ronald.
>
>
>>
>> ===
>> Mark Millard
>> marklmi at yahoo.com
>>
>>