Re: Core team statement on replication in PostgreSQL

On Thu, May 29, 2008 at 01:39:29PM -0700, David Fetter wrote:

> > I think the consensus in the core team was that having synchronous
> > log shipping in 8.4 would already be a worthwhile feature by itself.
>
> If that was in fact the consensus of the core team, and what I've been
> seeing from several core members in this thread makes that idea
> unclear, it's out of step with the stated goal of the feature. Having
> some kind of half-way, doesn't-actually-quite-work-out-of-the-box
> "replication" will make things worse and not better.

I don't agree with that. It seems to me that the stated goal is
fourfold:

1. Get something that is simple (out of the box).

2. Get something that is generally useful, even if not universally useful.

3. Get something that is implementable in stages, with each stage
representing an increase in functionality.

4. Aim for 8.4, but be realistic about chances.

It seems to me that sync. replication to a write-only standby actually
meets those goals. I can think of more than one case where I have
spent lots of time, money, or both attempting to achieve this goal
with various add-on hardware and software systems that mostly worked
except when they didn't. These additions were complicated to set up,
painful to use, and documented by sadists who couldn't write.

I agree that there are plenty of people unwilling to use a system that
requires additional hardware that mostly can't be used for other
things. But those people already have alternatives (maybe even more,
and simple ones, soon). The synchronous-needing crowd currently have
nothing. The proposed feature would be a huge improvement.

A

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