Re: pg_upgrade + streaming replication ?

On Tue, 2012-03-20 at 22:21 +0100, Henk Bronk wrote:
> actually rsync works fine on file level and is good for manual syncing.
> it check really the files with the stat command, so a bit change will trigger the copy
> in practice you need to keep an eye on compleetness of the rsync action.

Rsync still needs to examine the entire file. It has no information to
know that the file is the same on master and slave.

We could try to give it the appropriate information on which it can make
that assumption -- e.g. keep the timestamps the same so that rsync
assumes the contents are the same. But that seems fragile and I don't
see a good way of doing it, anyway.

We need a way to take a base backup of just the catalogs, essentially,
and leave the user data intact. Probably quite a few details to sort out
though.

Regards,
Jeff Davis