[sheepdog] [PATCH v2 0/2] block: deprecate the sheepdog driver

[Peter Krempa]

On Tue, Sep 22, 2020 at 18:42:52 +0100, Daniel Berrange wrote:
> On Tue, Sep 22, 2020 at 01:09:06PM -0400, Neal Gompa wrote:
> > On Tue, Sep 22, 2020 at 12:16 PM Daniel P. Berrangé <berrange at redhat.com> wrote:
> > >
> > > 2 years back I proposed dropping the sheepdog mailing list from the
> > > MAINTAINERS file, but somehow the patch never got picked up:
> > >
> > >   https://lists.gnu.org/archive/html/qemu-block/2018-03/msg01048.html
> > >
> > > So here I am with the same patch again.
> > >
> > > This time I go further and deprecate the sheepdog driver entirely.
> > > See the rationale in the second patch commit message.
> > >
> > > Daniel P. Berrangé (2):
> > >   block: drop moderated sheepdog mailing list from MAINTAINERS file
> > >   block: deprecate the sheepdog block driver
> > >
> > >  MAINTAINERS                |  1 -
> > >  block/sheepdog.c           | 15 +++++++++++++++
> > >  configure                  |  5 +++--
> > >  docs/system/deprecated.rst |  9 +++++++++
> > >  4 files changed, 27 insertions(+), 3 deletions(-)
> > >
> > > --
> > > 2.26.2
> > >
> > >
> > 
> > I don't know of anyone shipping this other than Fedora, and I
> > certainly don't use it there.
> > 
> > Upstream looks like it's unmaintained now, with no commits in over two
> > years: https://github.com/sheepdog/sheepdog/commits/master
> > 
> > Can we also get a corresponding change to eliminate this from libvirt?
> 
> This is only deprecation in QEMU, the feature still exists and is
> intended to be as fully functional as in previous releases.
> 
> Assuming QEMU actually deletes the feature at end of the deprecation
> cycle, then libvirt would look at removing its own support.

There are two sheepdog-related bits in libvirt which are IMO completely
separate:

1) the blockdev backend handling for the 'sheepdog' protocol driver

 This is the one connected to qemu's deprecation, but until there is a
 qemu version where sheepdog wasn't deprecated/removed supported by
 libvirt we can't really do much about it.

 On the other hand it's just a few generators of arguments for
 -drive/-blockdev so the burden is very low.

2) the sheepdog storage driver

 This one is completely separate from qemu and we can decide to
 deprecate/delete it at our own schedule as it will not influence the
 ability to start VMs.

 The last non-housekeeping commit in that driver seems to be dated:
 Thu Jun 18 16:20:42 2015

 Similarly the burden of keeping this around is low, but I would not bat
 an eye if we remove it right away even.