Greetings,
* Andres Freund (andres@anarazel.de) wrote:
> On 2019-04-22 14:26:40 -0400, Stephen Frost wrote:
> > I'm disappointed that the concerns about the trouble that end users are
> > likely to have with this didn't garner more discussion.
>
> My impression is that endusers are having a lot more trouble due to
> important backup/restore features not being in core/pg_basebackup, than
> due to external tools having a harder time to implement certain
> features.
I had been referring specifically to the concern I raised about
incremental block-level backups being added to pg_basebackup and how
that'll make using pg_basebackup more complicated and therefore more
difficult for end-users to get right, particularly if the end user is
having to handle management of the association between the full backup
and the incremental backups. I wasn't referring to anything regarding
external tools.
> Focusing on external tools being able to provide all those
> features, because core hasn't yet, is imo entirely the wrong thing to
> concentrate upon. And it's not like things largely haven't been
> implemented in pg_basebackup for fundamental architectural reasons.
> It's because we've built like 5 different external tools with randomly
> differing featureset and licenses.
There's a few challenges when it comes to adding backup features to
core. One of the reasons is that core naturally moves slower when it
comes to development than external projects do, as was discusssed
earlier on this thread. Another is that, when it comes to backup,
specifically, people want to back up their *existing* systems, which
means that they need a backup tool that's going to work with whatever
version of PG they've currently got deployed and that's often a few
years old already. Certainly when I've thought about features that we'd
like to see and considered if there's something that could be
implemented in core vs. implemented outside of core, the answer often
ends up being "well, if we do it ourselves then we can make it work for
PG 9.2 and above, and have it working for existing users, but if we work
it in as part of core, it won't be available until next year and only
for version 12 and above, and users can only use it once they've
upgraded.."
Thanks,
Stephen