Re: Core team statement on replication in PostgreSQL

On Fri, 2008-05-30 at 01:10 -0400, Tom Lane wrote:
> Greg Smith <gsmith(at)gregsmith(dot)com> writes:
> > I fully accept that it may be the case that it doesn't make technical
> > sense to tackle them in any order besides sync->read-only slaves because
> > of dependencies in the implementation between the two.
>
> Well, it's certainly not been my intention to suggest that no one should
> start work on read-only-slaves before we finish the other part. The
> point is that I expect the log shipping issues will be done first
> because they're easier, and it would be pointless to not release that
> feature if we had it.

Agreed.

I'm arriving late to a thread that seems to have grown out of all
proportion.

AFAICS streaming WAL and hot standby are completely orthogonal features.
Streaming WAL is easier and if NTT can release their code to open source
we may get this in the Sept commit fest. Hot Standby is harder and it
was my viewpoint at PGCon that we may not have a perfect working version
of this by the end of 8.4. We are very likely to have something working,
but maybe not the whole feature set as we might wish to have. I expect
to be actively working on this "soon". I definitely do want to see WAL
streaming going in as early as possible and before end of 8.4, otherwise
code conflicts and other difficulties are likely to push out the 8.4
date and/or Hot Standby.

So as I see it, Tom has only passed on my comments on this, not added or
removed anything. The main part of the announcement was really about
bringing the WAL streaming into core and effectively favouring it over a
range of other projects.

Can we all back off a little on this for now? Various concerns have been
validly expressed, but it will all come good AFAICS.

--
Simon Riggs www.2ndQuadrant.com
PostgreSQL Training, Services and Support