| From: | Simon Riggs <simon(at)2ndquadrant(dot)com> |
|---|---|
| To: | Markus Wanner <markus(at)bluegap(dot)ch> |
| Cc: | Robert Hodges <robert(dot)hodges(at)continuent(dot)com>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Bruce Momjian <bruce(at)momjian(dot)us>, Jens-Wolfhard Schicke <drahflow(at)gmx(dot)de>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Transaction-controlled robustness for replication |
| Date: | 2008-08-13 14:00:24 |
| Message-ID: | 1218636024.5343.350.camel@ebony.2ndQuadrant |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Wed, 2008-08-13 at 15:38 +0200, Markus Wanner wrote:
> Simon Riggs wrote:
> > Classification of Replication Techniques
>
> Thanks for your classifications. It helps a great deal to clarify.
>
> > Type 2 is where you ship the WAL (efficient) then use it to reconstruct
> > SQL (flexible) and then apply that to other nodes. It is somewhat harder
> > than type 1, but requires less infrastructure (IMHO). Definitely
> > requires less data shipping from Primary node, so very possibly more
> > efficient.
>
> What leads you to that conclusion? AFAICT a logical format, specifically
> designed for replication is quite certainly more compact than the WAL
> (assuming that's what you mean by "less data").
Possibly, but since we are generating and writing WAL anyway that's not
a completely fair comparison.
> Which of IBM's and Oracle's products are you referring to?
IBM DB2 HADR, QReplication.
Oracle Streams 10g+, Data Guard Logical and Physical Standby
All of which I've personally used, except for Oracle Streams10g, which I
investigated thoroughly for a client about 4 years ago.
--
Simon Riggs www.2ndQuadrant.com
PostgreSQL Training, Services and Support
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Tom Lane | 2008-08-13 14:00:29 | Re: Replay attack of query cancel |
| Previous Message | Magnus Hagander | 2008-08-13 13:59:22 | Re: Replay attack of query cancel |