Horton

Re: [PATCH 10/16] Introduce the concept that wal has a 'origin' node

Andres Freund <andres@2ndquadrant.com>

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From: Andres Freund <andres@2ndquadrant.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Simon Riggs <simon@2ndquadrant.com>, Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>, Kevin Grittner <Kevin.Grittner@wicourts.gov>, pgsql-hackers@postgresql.org, Daniel Farina <daniel@heroku.com>, Tom Lane <tgl@sss.pgh.pa.us>
Date: 2012-06-20T13:21:54Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Don't waste the last segment of each 4GB logical log file.

  2. Stamp HEAD as 9.3devel.

  3. Wake WALSender to reduce data loss at failover for async commit.

  4. Make the visibility map crash-safe.

On Wednesday, June 20, 2012 03:19:55 PM Robert Haas wrote:
> On Wed, Jun 20, 2012 at 5:47 AM, Simon Riggs <simon@2ndquadrant.com> wrote:
> > The idea that logical rep is some kind of useful end goal in itself is
> > slightly misleading. If the thought is to block multi-master
> > completely on that basis, that would be a shame. Logical rep is the
> > mechanism for implementing multi-master.
> 
> If you're saying that single-master logical replication isn't useful,
> I disagree.  Of course, having both single-master and multi-master
> replication together is even more useful.  But I think getting even
> single-master logical replication working well in a single release
> cycle is going to be a job and a half.  Thinking that we're going to
> get MMR in one release is not realistic.  The only way to make it
> realistic is to put MMR ahead of every other goal that people have for
> logical replication, including robustness and stability.  It's
> entirely premature to be designing features for MMR when we don't even
> have the design for SMR nailed down yet.  And that's even assuming we
> EVER want MMR in core, which has not even really been argued, let
> alone agreed.
I agree it has not been agreed uppon, but I certainly would consider 
submitting a prototype implementing it an argument for doing it ;)

Andres
-- 
 Andres Freund	                   http://www.2ndQuadrant.com/
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