On 2015-05-30 14:10:36 -0400, Robert Haas wrote:
> It's clear - at least to me - that we need to put more resources into
> stabilizing the new multixact system. This is killing us. If we can't
> stabilize this, people will go use some other database.
I agree. Perhaps I don't see things quite as direly, but then I didn't
just spend weeks on the issue. I remember that I was incredibly
frustrated around 9.3.2 because I'd spent weeks on fixing issued around
this and it just never seemed to stop.
> Equally importantly, we need to make sure that we never release
> something comparably broken ever again. And that's why I'm not
> sanguine about shipping what we've got without adequate reflection.
I think you're inferring something wrong here. A beta/alpha *is* getting
feedback on how good/bad things are. It's just one source of such
information, but we don't have that many others.
As explained in the email I sent before this, I think a lot of the
problems come from too complex code (with barely any testing). But we're
not going to be able to clean this up in 9.5. This will be a longer term
effort.
If we, without further changes, decide to let the release slip to, say,
Q1 2016, the only thing that'll happen is to happen that 9.6 will have
larger, more complex features. With barely any additional review and
testing done. There was very little, if any, additional testing/review
outside jsonb due to the 9.4 slippage.
I don't think the problems have much to do with the release schedule.
> What, in this release, could break things badly?
> RLS?
Mostly localized to users of the feature. Niche use case.
> Grouping sets?
Few changes to code unless grouping sets are used.
> Heikki's WAL format changes?
Yes, that's quite invasive. On the other hand, I can't think of another
feature that had as much invested in tooling to detect problem.
What's more:
* Upsert - it's probably the most complex feature in 9.5. It's quite localized though.
* The locking changes, a good amount of potential for subtle problems
* The signal handling, sinval, client communication changes. Little to none problems so far, but it's complex stuff.
Thesechanges are an example of potential for problems due to changes to reduce complexity...
Greetings,
Andres Freund
