Message-ID: <4671CB7A.6000909@emolecules.com>
Date: Thu, 14 Jun 2007 16:12:58 -0700
From: "Craig A. James" <cjames@emolecules.com>
User-Agent: Thunderbird 1.5.0.12 (X11/20070509)
MIME-Version: 1.0
To: pgsql-performance@postgresql.org
Subject: Replication
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

Looking for replication solutions, I find:

Slony-I
  Seems good, single master only, master is a single point of failure,
  no good failover system for electing a new master or having a failed
  master rejoin the cluster.  Slave databases are mostly for safety or
  for parallelizing queries for performance.  Suffers from O(N^2) 
  communications (N = cluster size).

Slony-II
  Seems brilliant, a solid theoretical foundation, at the forefront of
  computer science.  But can't find project status -- when will it be
  available?  Is it a pipe dream, or a nearly-ready reality?

PGReplication
  Appears to be a page that someone forgot to erase from the old GBorg site.

PGCluster
  Seems pretty good, but web site is not current, there are releases in use
  that are not on the web site, and also seems to always be a couple steps
  behind the current release of Postgres.  Two single-points failure spots,
  load balancer and the data replicator.

Is this a good summary of the status of replication?  Have I missed any important solutions or mischaracterized anything?

Thanks!
Craig

(Sorry about the premature send of this message earlier, please ignore.)