Re: Core team statement on replication in PostgreSQL

David Fetter <david@fetter.org> writes:
> On Thu, May 29, 2008 at 08:46:22AM -0700, Joshua D. Drake wrote:
>> The only question I have is... what does this give us that PITR
>> doesn't give us?

> It looks like a wrapper for PITR to me, so the gain would be ease of
> use.

A couple of points about that:

* Yeah, ease of use is a huge concern here.  We're getting beat up
because people have to go find a separate package (and figure out
which one they want), install it, learn how to use it, etc.  It doesn't
help that the most mature package is Slony which is, um, not very
novice-friendly or low-admin-complexity.  I personally got religion
on this about two months ago when Red Hat switched their bugzilla
from Postgres to MySQL because the admins didn't want to deal with Slony
any more.  People want simple.

* The proposed approach is trying to get to "real" replication
incrementally.  Getting rid of the loss window involved in file-by-file
log shipping is step one, and I suspect that step two is going to be
fixing performance issues in WAL replay to ensure that slaves can keep
up.  After that we'd start thinking about how to let slaves run
read-only queries.  But even without read-only queries, this will be
a useful improvement for HA/backup scenarios.
        regards, tom lane