Re: Future In-Core Replication

On Mon, Apr 30, 2012 at 11:43 PM, Josh Berkus <josh(at)agliodbs(dot)com> wrote:

> Well, this *is* the purpose of the cluster-hackers group

Well, I tried all available means to discuss my ideas before
organising an external meeting. You can think of the InCore meeting as
an extension of the cluster hackers meeting if you wish.

> What puts me off about this "let's start from first principles" approach
> is that in our community we have years of experience (in a couple cases,
> over a decade) with logical-level replication.  It seems like the last
> thing we need is Yet Another PostgreSQL Replication System, started over
> from scratch and years away from being production quality.  Don't we
> have enough external replication systems with not enough developers
> behind them?

I've tried very hard to express my admiration and respect for
developers of many replication systems both personally when we meet in
person and on list. And I've mentioned that I'd like to include as
many ideas as possible in an in-core approach. Yes, we have many
external replication systems. Many, many people have expressed the
desire for more coherent features in core.

I believe we can achieve production quality code in 1, maybe 2
releases. That is only possible by building on what we already have
and reusing the concepts, experience and perhaps even code from other
projects. We are closer to that than your statement allows. Yes, we
have enough external replication systems and that is one reason why we
need to put things in core and not just create another external
system.

> Even if improving an existing replication system proves to be
> impossible, it would make more sense to start with an analysis of the
> strengths and deficiencies of Slony, Londiste, Bucardo, etc., than with
> some kind of "clean-room" approach.

I'm not sure why you think I would *not* be starting with that analysis.

I look forward to discussing this in person, where I'm sure it will be easier.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
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