[Pkg-zfsonlinux-devel] About downstream patches on debian packages from zfsonlinux.org repository.

[Aron Xu]

On Wed, Aug 24, 2016 at 7:12 PM, Petter Reinholdtsen <pere at hungry.com> wrote:
> [Carlos Alberto Lopez Perez]
>> Hi,
>>
>> Me and Peter have been checking the downstream patches that the Debian
>> packages from the zfsonlinux.org repository carry for Debian jessie [1].
>> The goal is ensuring a smooth transition/upgrade to the packages that
>> hopefully Debian stretch will ship.
>>
>> Personally, I don't like at all the idea of merging new features still
>> not upstreamed. But this can be discussed.
>
> Thank you for the overview.  A similar one for the Ubuntu packages would
> be nice.  We know they diverge from Debian by providing prebuild kernel
> modules, but are there other differences?  Anything we should care
> about.
>

Yes, they binary modules are built from upstream stable release +
cherry-pick of upstreamed patches (some of them may be authored by
Canonical people).

>> Maybe I'm overlooking something, and what I think is just a new feature
>> that can wait for upstream to merge it, it is a critical feature for
>> someone using it already in production.
>
> Waiting for upstream to merge changes make sense if merging will happen.
> I do not have any experience with the ZFS on Linux upstream, nor with
> the OpenZFS upstream.  What is their relationship with each other?  Do
> patches flow well between the various open ZFS projects?  I notice there
> are no-one from ZoL speaking at the upcoming OpenZFS Developer Summit.
> Is that because the ZoL group is less active, or nothing to worry about?
>

ZoL is merging changes from other ZFS projects especially
illumos-gate, I don't think this is something to worry.

>> So, the purpose of this mail is to ask for feedback regarding this.  I
>> did a quick review of the patches and annotated those that I think we
>> should try to merge and those I think we should skip until merged
>> upstream. Feel free to add your comments on the pad itself or to reply
>> to this e-mail.
>
> It seem like a hard balance to find what to include and what to skip.
> On one hand I believe all of us making Debian packages for ZFS should
> try to join forces, ie the Debian, Ubuntu and ZFS on Linux deb packages
> (only Turbo?) and try to make a great set of packages for use by all
> Debian derivates.  Because we are so few, focusing on one set of
> packages or at least reduce the differences between the three sets of
> pacakges would be a good thing to save labour.  And because we are so
> few, we should not give ourself extra work by diverting from upstream.
> As far as I can tell, we do not have much manpower available to fix
> stability and security issues introduced in Debian specific patches.  So
> we should limit the diversion from upstream and the other deb packages
> to a minimum, to be able to share the load if making fixes.
>

I'm on the Ubuntu team us well (though not active enough either),
trying to join the forces is always a target. But we don't have enough
hands here to get things in sync, and Ubuntu as a project backed by a
company cannot always wait for us.

> But we should also provide the features users expect and need to get ZFS
> working out of the box with the boot systems, SMB, NFS etc, and in some
> cases provide a test bed for upstream to test out changes in the code if
> we consider it a service to our users.  But in these cases we must
> actively try to get changes back upstream to avoid having to maintain
> such patches in the future.
>

Personally I don't like the idea that we merge things in kernel land
that's not acked by upstream, but would be happy to give user land
stuff a test bed, probably we can mark those part as experimental and
have our users be warned.

> Introducing locla patches make most sense if the patches are going to
> get into upstream in the future.  We need to actively work to reduce the
> difference between the Debian packages and the upstream source code.
> Otherwise we will fail sooner or later, when we no longer are able to
> update the zfs packages in Debian in a timely fasion or expose our users
> for unexpected stability or security issues we lack the man power to
> rapidly respond to.  Who can spend some time trying to get the patches
> from Debian, Ubuntu and ZoL debs into the official ZoL upstream source?
>
> How can we set up a process to make it easier to push changes back
> upstream.  I read from Turbo Fredrikson that this is non-trivial today.
> Is there something we can do from the Debian side to make it easier?
> Perhaps someone from this team should show up in San Francisco in a
> month to join the OpenZFS Developer Summit?  Should we try to organize
> developer gatherings for the ZFS people in ZoL, Ubuntu and Debian to
> increase the chance of these people working together?  Can we set up
> some test environments to make it easier for the upstream developers to
> know if patches are likely to break something or not?  Are there other
> ideas?
>

I'm going to the OpenZFS Developer Summit, with Collin King who does
many work on Ubuntu. What would do you expect me to organize?



Regards,
Aron