Re: WIP partial replication patch
Boszormenyi Zoltan <zb@cybertec.at>
From: Boszormenyi Zoltan <zb@cybertec.at>
To: Andres Freund <andres@anarazel.de>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Hans-Juergen Schoenig <hs@cybertec.at>
Date: 2010-08-14T06:40:24Z
Lists: pgsql-hackers
Andres Freund írta: > On Fri, Aug 13, 2010 at 09:36:00PM +0200, Boszormenyi Zoltan wrote: > >> Tom Lane írta: >> >>> Boszormenyi Zoltan <zb@cybertec.at> writes: >>> >>> >>>> attached is a WIP patch that will eventually implement >>>> partial replication, with the following syntax: >>>> >>> This fundamentally cannot work, as it relies on system catalogs to be >>> valid during recovery. >>> >> Just like Hot Standby, no? What is the difference here? >> Sorry for being ignorant. >> > In HS you can only connect after youve found a restartpoint - only > after that you know that you have reached a consistent point for the > system. > And in this patch, the startup process only tries to connect after signalling the postmaster that a consistent state is reached. And the connection has a reasonable timeout built in. > I think this is fixable by keeping more wal on the standby's but I > need to think more about it. > > Andres > > Best regards, Zoltán Böszörményi