Re: Postgresql replication

On Wed, Aug 24, 2005 at 11:54:42AM -0400, Chris Browne wrote:
> There is a Slony-II project ongoing that is trying to construct a
> more-or-less synchronous multimaster replication system (where part of
> the cleverness involves trying to get as much taking place in an
> asynchronous fashion as possible) that would almost certainly be of no
> use to your "use case."

Just to emphasise this point: assuming we ever get Slony-II to work,
it is all but guaranteed to be useless for cases like the one that
started this thread: it'll simply require very fast network
connections to work.  I've had more than one person ask me when
multi-site multimaster is coming, and my answer is always, "Have you
started work on it yet?"  I think there might be a way to hack up
Slony-I to do it -- Josh Berkus gave me a quick outline while at
OSCON that made me think it possible -- but AFAIK, nobody is actually
doing that work.

It's worth noting that single-origin master-slave async replication
is tricky, but by no means impossible.  Multi-master _anything_ is
hard, no question about it; and it more or less always imposes some
overhead that you won't like.  The question is merely whether you
want to pay that price.

A

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