Re: [pve-devel] [PATCH storage] Revert "workaround zfs create -V error for unaligned sizes"

[Fiona Ebner <f.ebner@proxmox.com>]

Am 14.06.23 um 13:44 schrieb Aaron Lauterer:
> On 6/14/23 13:38, Thomas Lamprecht wrote:
>> Am 14/06/2023 um 13:28 schrieb Aaron Lauterer:
>>> This reverts commit cdef3abb25984c369571626b38f97f92a0a2fd15.
>>>
>>> The bug should be fixed by now [0]. The reproducer doesn't cause any
>>> issues in my tests.
>>>
>>> [0] https://github.com/openzfs/zfs/issues/8541
>>
>> hmm, torn on this one; 1 MB aligned images sound not to bad for
>> various things,
>> and the extra size is rather negligible most of the time so we can
>> mostly lose
>> here, otoh. it should be callers decision if storage works fine now..
>>
>>>
>>> Signed-off-by: Aaron Lauterer <a.lauterer@proxmox.com>
>>> ---
>>> AFAICT this has an affect on EFI disks which after this revert will be
>>> 528k and not 1M. Similar as if we would store it as a .raw file.
>>>
>>
>> that sounds like it _could_ break stuff..
>>
>> @fiona: what was the state with local storage migration and those disk
>> size
>> mismatches? Or anything else coming to your mind?
> 
> I did a few tests in the meantime. An EFI disk on a directory based
> storage will be 528 K and can be moved to a ZFS storage with this patch.
> Without it, it will fail, similar to RBD which needs a 1M min size IIRC.

Yes, drive mirror will fail if the source and target volume don't have
the exact same size: https://bugzilla.proxmox.com/show_bug.cgi?id=3227
so this would be an improvement. Although the proper fix for that bug
would need to be made in drive mirror (e.g. by adding an option to allow
larger target image).

Offline storage export/import for ZFS is currently limited to ZFS<->ZFS
anyways.

I'm not aware of any issues, but the alignment has been there for a
while now ;)

There's also similar padding in volume_resize(). Does ZFS also round up
automatically there now or do we need to keep that?