On Tue, 28 Jul 2026 at 18:22, Nathan Hartman <[email protected]>
wrote:

> On Tue, Jul 28, 2026 at 9:58 AM Nathan Hartman <[email protected]>
> wrote:
> >
> > On Tue, Jul 28, 2026 at 8:10 AM Daniel Sahlberg
> > <[email protected]> wrote:
> > >
> > > Den fre 24 juli 2026 kl 21:03 skrev Daniel Sahlberg <
> [email protected]>:
> > >>
> > >> Den fre 24 juli 2026 kl 18:52 skrev Nathan Hartman <
> [email protected]>:
> > >>>
> > >>> On Fri, Jul 24, 2026 at 11:52 AM Ivan Zhakov <[email protected]>
> wrote:
> > >>> >
> > >>> > On Fri, 24 Jul 2026 at 15:06, Branko Čibej <[email protected]>
> wrote:
> > >>> >>
> > >>> >> On 24. 7. 2026 13:57, Daniel Sahlberg wrote:
> > >>> >>
> > >>> >> Den fre 24 juli 2026 kl 13:30 skrev Branko Čibej <
> [email protected]>:
> > >>> >>>
> > >>> >>> On 24. 7. 2026 13:23, Branko Čibej wrote:
> > >>> >>>
> > >>> >>> On 24. 7. 2026 13:20, Ivan Zhakov wrote:
> > >>> >>>
> > >>> >>> On Sat, 18 Jul 2026 at 18:27, Nathan Hartman <
> [email protected]> wrote:
> > >>> >>> > I'm glad there's a good bit of housecleaning going on around
> here.
> > >>> >>> > We've accumulated so much cruft over the years, it makes my
> > >>> >>> > head spin. +1 to axe the ctypes bindings.
> > >>> >>>
> > >>> >>> Speaking of cleanups, another candidate comes to mind: the BDB
> FS backend. I think now would be an appropriate time to remove it:
> > >>> >>>
> > >>> >>>
> > >>> >>>
> > >>> >>> We can't remove it before 2.0. It doesn't matter that it's
> deprecated, it's part of the published 1.0 feature set.
> > >>> >>>
> > >>> >>>
> > >>> >>>
> > >>> >>> Just to be clear: the existence of the BDB back-end is
> equivalent to a public API. We have many deprecated public APIs that we
> can't remove for the same reason.
> > >>> >>>
> > >>> >>> -- Brane
> > >>> >>
> > >>> >>
> > >>> > [...]
> > >>> >>
> > >>> >> This was discussed previously [1] and we even received a bug
> report from FreeBSD that it doesn't work [2]. In the first link Yasuhito
> Futatsuki was of the opposite opinion: the FS type is not a public API. I
> tend to side with him but I could be convinced otherwise.
> > >>> >>
> > >>> >> As Yasuhito point out, SVN_FS_TYPE_BDB is a public API which we
> need to keep. I didn't study details but I assume the code in
> libsvn_fs_base only implement a filesystem API reachable via the fs loader
> (this is way over my paygrade so please educate me if I misunderstand
> something!). In that case, we won't break anyone's code so anything that
> compiles under 1.14 will still compile under 1.16, but it it would not be
> able to load the BDB FS backend (just as if you didn't compile it in the
> first place).
> > >>> >>
> > >>> >> Of course - we would force anyone using a BDB backend to do a
> dump-and-reload cycle as part of their upgrade.
> > >>> >>
> > >>> >> Provided my understanding above is correct, I'm in favour of
> removing BDB.
> > >>> >>
> > >>> >>
> > >>> >>
> > >>> >> What do we do with older clients that link with libsvn_fs_base
> when a library upgrade makes that go away? At the very least we'd have to
> keep a stub that implements all exported functions, or we break the ABI.
> > >>> >>
> > >>> >
> > >>> > As far as I see libsvn_fs_base functions are not publicly
> exported. We have some BDB FS specific functions [1] in libsvn_fs, but they
> already stub to newer API and I agree we should keep them.
> > >>> >
> > >>> >>
> > >>> >> In other words, even if we decide that removing BDB support isn't
> an API violation, we can't do this in 1.15 because it's not a trivial
> change of removing a directory and a couple lines from build.conf.
> > >>> >>
> > >>> > I agree and I don't think we should be doing anything about BDB in
> 1.15 at this point (except for release notes). The proposed plan was about
> removing it in trunk / 1.16.
> > >>> >
> > >>> > [1]:
> https://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_fs/fs-loader.c?revision=1936528&pathrev=1936528&view=markup#l786
> > >>> >
> > >>> > --
> > >>> > Ivan Zhakov
> > >>>
> > >>>
> > >>> This was discussed several times before, such as [1], [2].
> > >>>
> > >>> Arguments in favor of removing BDB:
> > >>>
> > >>> (1) It has been deprecated for a long time.
> > >>>
> > >>> (2) AFAICT most devs are no longer testing BDB so maybe it works, or
> > >>> maybe it bitrotted.
> > >>>
> > >>> (3) Last I checked, some kind of registration was needed to get the
> > >>> official sources?
> > >>>
> > >>> (4) It might not have many (or any) users anymore.
> > >>>
> > >>> Arguments against removing it:
> > >>>
> > >>> (1) API guarantees...
> > >>>
> > >>> (2) Questions about what's involved in actually ripping it out.
> > >>>
> > >>> (3) Users with BDB-backed repos would need to dump and load them
> > >>> BEFORE we remove it...
> > >>>
> > >>> ...and that means we need to give very clear, advance notice.
> > >>>
> > >>> So this is my suggestion: For now, let's start by making the
> > >>> announcement together with the 1.15.0 release. I suggest to put the
> > >>> announcement in the 1.15 release notes as well as creating a separate
> > >>> news item for it. In the announcement, we won't commit to removing it
> > >>> by a specific date or release. We'll just convey that its removal is
> > >>> being planned and may be imminent.
> > >>>
> > >>> After the announcement is made, Let's take as long as we need to
> > >>> figure out the issues of API guarantees, how/what to remove, etc.
> > >>> There's no rush to do the actual removal, but I think the
> announcement
> > >>> needs to give users as much time as possible.
> > >>>
> > >>> Proposed initial draft of announcement:
> > >>>
> > >>> [[[
> > >>>
> > >>> IMPORTANT NOTICE: Subversion's Berkeley DB repository backend (BDB)
> > >>> has been deprecated since Subversion 1.8 (13 years) and is planned
> for
> > >>> REMOVAL with a future Subversion release line. It will not be
> possible
> > >>> to access BDB-backed Subversion repositories after upgrading to a
> > >>> Subversion release that no longer supports it. The Subversion 1.15.x
> > >>> release line may be the last minor release line to support the BDB
> > >>> backend.
> > >>>
> > >>> Users who have BDB-backed Subversion repositories should upgrade them
> > >>> to the newer FSFS backend as soon as possible to avoid disruption.
> > >>> FSFS has been the default since Subversion 1.2 (21 years). This
> > >>> requires to "dump" the repository using a Subversion release that
> > >>> supports BDB and then to "load" the repository using any recent
> > >>> Subversion release. For details, please see the FAQ entry "How do I
> > >>> convert my repository from using BDB to FSFS or from FSFS to BDB?":
> > >>> https://subversion.apache.org/faq.html#bdb-fsfs-convert
> > >>>
> > >>> ]]]
> > >>>
> > >>> Commenting on my own initial draft:
> > >>>
> > >>> Instead of sending them to the FAQ, maybe we'd want to write clear
> > >>> backup/dump/load instructions directly in the announcement?
> > >>>
> > >>> Do we want to point out that the BDB backend might not be as well
> > >>> tested as FSFS these days?
> > >>>
> > >>> WDYT?
> > >>
> > >>
> > >> I think this is a good plan. I would prefer to keep the announcement
> as short as possible and link to the FAQ, improving that if needed.
> > >>
> > >> I seem to remember that we at one point has talked about the lack of
> testing - but that may just be on the mailing list..? I would probably not
> mention it in the announcement - either something is supported or it is NOT
> supported.
> > >>
> > >> Cheers,
> > >> Daniel
> > >>
> > >>
> > >>>
> > >>>
> > >>> [1] "Berkely DB precompiled for Windows"
> > >>>     Posted to dev@ on 26 Sept 2024
> > >>>
> https://lists.apache.org/thread/m4o5l9rntc98y6s8wrhsn329by9bhr19
> > >>>     Continued here (disconnected in the archives):
> > >>>
> https://lists.apache.org/thread/99zo1wq003109p06dt1tcxyzd7cyyw32
> > >>>     and here:
> > >>>
> https://lists.apache.org/thread/7plrvmhk3c0jvhkq1tfwds8j4tmlgslc
> > >>>
> > >>> [2] "Removing BDB support from 1.15"
> > >>>     Posted to dev@ on 18 Mar 2025
> > >>>
> https://lists.apache.org/thread/kn0yw4f8p6tn2tzq4obr5r5v609g6g1m
> > >>>
> > >>> Cheers,
> > >>> Nathan
> > >
> > >
> > > It has been over four days and no further discussion on this thread so
> I'd like to try making a summary. The last technical comment was made by
> Ivan answering Brane's concerns about modifying public API ("libsvn_fs_base
> functions are not publicly exported. We have some BDB FS specific functions
> in libsvn_fs, but they already stub to newer API and I agree we should keep
> them").
> > >
> > > @Branko Čibej Does this satisfy your concerns?
> > >
> > > Anyone else?
> > >
> > > Cheers,
> > > Daniel
> > >
> > >
> > >
> >
> > Currently 'svnadmin help create' has this to say about the --fs-type arg:
> >
> >   --fs-type ARG            : type of repository:
> >                              'fsfs' (default), 'bdb' or 'fsx'
> >                              CAUTION: FSX is for EXPERIMENTAL use only!
> >
> > Perhaps there should also be a "WARNING: BDB will be removed in an
> > upcoming release?" or something to that effect?
>
>
> I have drafted a notice of BDB's impending removal in the 1.15 release
> notes
> in r1936672.
>
> The text looks good to me!

Thanks!

-- 
Ivan Zhakov

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