From: | Andres Freund <andres(at)2ndquadrant(dot)com> |
---|---|
To: | pgsql-hackers(at)postgresql(dot)org |
Cc: | "Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov>, "Simon Riggs" <simon(at)2ndquadrant(dot)com>, "Robert Haas" <robertmhaas(at)gmail(dot)com>, "Daniel Farina" <daniel(at)heroku(dot)com>, "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
Subject: | Re: [PATCH 10/16] Introduce the concept that wal has a 'origin' node |
Date: | 2012-06-19 22:19:23 |
Message-ID: | 201206200019.23933.andres@2ndquadrant.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
On Wednesday, June 20, 2012 12:15:03 AM Kevin Grittner wrote:
> Simon Riggs <simon(at)2ndQuadrant(dot)com> wrote:
> > If we use WAL in this way, multi-master implies that the data will
> > *always* be in a loop. So in any configuration we must be able to
> > tell difference between changes made by one node and another.
>
> Only if you assume that multi-master means identical databases all
> replicating the same data to all the others. If I have 72 master
> replicating non-conflicting data to one consolidated database, I
> consider that to be multi-master, too.
> ...
> Of course, none of these databases have the same OID for any given
> object, and there are numerous different schemas among the
> replicating databases, so I need to get to table and column names
> before the data is of any use to me.
Yes, thats definitely a valid use-case. But that doesn't preclude the other -
also not uncommon - use-case where you want to have different master which all
contain up2date data.
Andres
--
Andres Freund http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services
From | Date | Subject | |
---|---|---|---|
Next Message | Andres Freund | 2012-06-19 22:21:57 | Re: Backport of fsync queue compaction |
Previous Message | Kevin Grittner | 2012-06-19 22:15:03 | Re: [PATCH 10/16] Introduce the concept that wal has a 'origin' node |