Re: Synchronization levels in SR

On Wed, May 26, 2010 at 2:31 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> On Tue, 2010-05-25 at 23:59 -0400, Robert Haas wrote:
>> Quorum commit is definitely an extra knob, IMHO.
>
> No, its about three less, as I have explained.
>
> Explain your position, don't just demand others listen.

OK. In words of one syllable, your way still has all the same knobs,
plus some more.

You sketched out a design which still had a per-standby setting for
each standby, but IN ADDITION had a setting for a setting to control
quorum commit[1]. You also argued that we needed four options for
each transaction rather than three[2], and that we need a userset GUC
to control the behavior on a per-transaction basis[3]. Not one other
person has agreed that we need all of these options in the first
version of the patch. We don't. We can start with a sync rep patch
that does ONE thing and does it well, and we can add these other
things later. I don't think I'm going too far out on a limb when I say
that it is easier to get a smaller patch committed than it is to get a
bigger one committed, and it is less likely to have bugs.

[1] http://archives.postgresql.org/pgsql-hackers/2010-05/msg01347.php
[2] http://archives.postgresql.org/pgsql-hackers/2010-05/msg01333.php
[3] http://archives.postgresql.org/pgsql-hackers/2010-05/msg01334.php

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise Postgres Company