On Wed, Nov 21, 2018 at 03:47:22PM -0800, Andres Freund wrote: > Hi, > > I feel like we ought to trim the support for a few old versions from > pg_upgrade. In my particular case I don't really think it's reasonable > to test < 9.0 versions for pg_largeobject_metadata migrations. But I > think we should create a policy that's the default, leaving individual > cases aside. > > I can see a few possible policies: > > 1) Support upgrading from the set of releases that were supported when > the pg_upgrade target version was released. While some will argue that > this is fairly short, people above it can still upgrade ~10 years > worth of versions with a single intermediary upgrade. > 2) Same, but +2 releases or such. > 3) Support until it gets too uncomfortable. > 4) Support all versions remotely feasible (i.e. don't drop versions that > still can be compiled)
The way pg_upgrade works right now, 1), 2), and 4) basically make it impossible to change our storage format in any non-trivial way, and 3) is a "trivial case" in the sense that the first such non-trivial storage format change ends pg_upgrade support. Are we really that attached to how we store things? Best, David. -- David Fetter <david(at)fetter(dot)org> http://fetter.org/ Phone: +1 415 235 3778 Remember to vote! Consider donating to Postgres: http://www.postgresql.org/about/donate