Re: [PATCH 5/5] zfs extensible_dataset and large_blocks feature support

[Toomas Soome]

hi!
so what is the status of this last feature pair?  its the final bundle to get 
full support of modern openzfs to grub and since   zfs on all major players 
(illumos/zol/freebsd) support this feature, its only question of time when 
someone will step on this missing piece;)

rgds,
toomas

> On 04.05.2015, at 9:49, Toomas Soome <address@hidden> wrote:
> 
> 
>> On 04.05.2015, at 7:32, Andrei Borzenkov <address@hidden> wrote:
>> 
>> В Sun, 03 May 2015 22:47:40 +0300
>> Toomas Soome <address@hidden> пишет:
>> 
>>> 
>>>> On 03.05.2015, at 22:23, Andrei Borzenkov <address@hidden> wrote:
>>>> 
>>>>>> 
>>>>> 
>>>>> they do implement read support extensible dataset… instead of fixed DMU 
>>>>> types they dont specify type, making it possible to use fat zap objects 
>>>>> from bonus area. 
>>>>> 
>>>>> reference commit:
>>>>> https://github.com/illumos/illumos-gate/commit/2acef22db7808606888f8f92715629ff3ba555b9
>>>>> 
>>>> 
>>>> OK; just to be sure - there are several remaining uses of
>>>> DMU_OT_DSL_DATASET and DMU_OT_DSL_DIR; are these intentional?
>>> 
>>> 
>>> they *should* be ok. at least browsing and loading files from datasets 
>>> haven’t revealed other instances over the test time. but problem is, the 
>>> cases of zapify (when “normal” structure is wrapped as zap object) I have 
>>> seen, have been related to datasets using >128k recordsize, and its 
>>> possible some cases may have been missed - the grub zfs code and real zfs 
>>> code are not exactly easy to compare. at least so far I haven’t seen bugs 
>>> related to this nor received any reports. the basic symptom can be either 
>>> message about wrong type or “missing” directory entry in listing.
>>> 
>> 
>> 
>> Can https://savannah.gnu.org/bugs/?44448 be somehow related?
> 
> without grub debug=zfs its impossible to say - guessing there is not really 
> helpful:) altho in general, feature check for label should generate error 
> message if pool has enabled features not supported by version of grub used 
> there.
> 
> basically, my first suggestion to cases like that is to set debug=zfs in grub 
> and ask user to provide that debug output.
> 
> rgds,
> toomas
> 
>