Re: [PATCH 10/16] Introduce the concept that wal has a 'origin' node

On Wed, Jun 20, 2012 at 5:47 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> The idea that logical rep is some kind of useful end goal in itself is
> slightly misleading. If the thought is to block multi-master
> completely on that basis, that would be a shame. Logical rep is the
> mechanism for implementing multi-master.

If you're saying that single-master logical replication isn't useful,
I disagree. Of course, having both single-master and multi-master
replication together is even more useful. But I think getting even
single-master logical replication working well in a single release
cycle is going to be a job and a half. Thinking that we're going to
get MMR in one release is not realistic. The only way to make it
realistic is to put MMR ahead of every other goal that people have for
logical replication, including robustness and stability. It's
entirely premature to be designing features for MMR when we don't even
have the design for SMR nailed down yet. And that's even assuming we
EVER want MMR in core, which has not even really been argued, let
alone agreed.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company