Re: 7.4? - Mailing list pgsql-general

You might want to look at my replication talk:

    http://candle.pha.pa.us/main/writings/pgsql/replication.pdf

Basically, single-master uses async because it is faster, but when you
need multimaster, you usually need sync or a Postgres-R-type approach.

Seems there too may replication needs, so even Postgres-R will remain a
plugin option for PostgreSQL, like the other replication solutions.

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Herv� Piedvache wrote:
> Le Mercredi 26 F?vrier 2003 07:52, Tom Lane a ?crit :
> > Neil Conway <neilc@samurai.com> writes:
> > > On Tue, 2003-02-25 at 22:44, Ed L. wrote:
> > >> And do I understand correctly the replication to be eventually
> > >> included will be an embedded syncronous replication solution based on
> > >> Postgres-R and the Spread GCS?
> > >
> > > No, I don't think that's set in stone (although I can't speak for the
> > > core team). While I think Postgres-R is promising, there might be room
> > > for additional replication implementations that cater to different sets
> > > of requirements.
> >
> > There absolutely *is* room for multiple replication implementations.
> > AFAICS there's no one-size-fits-all approach.  I did and still do like
> > Postgres-R as a pretty useful approach, but it should not be mistaken
> > for The One True Path.
> >
> > Also, there are nontrivial licensing issues involved.  The PG-R design
> > depends on an underlying "group communication" system, which is a
> > nontrivial bit of software that none of the core team wants to rewrite.
> > But none of the available GC systems are BSD-license open source.  We
> > had had some hopes of getting Spread to offer BSD terms, but that seems
> > to have fallen through.  So right now, PG-R is on the outside looking
> > in, as far as inclusion in the core distribution goes :-(
> >
> >             regards, tom lane
>
> You mean the PG-R project will no be included in the PostgreSQL project
> unless someone rewrite the Spread GCS concept or similar system in a BSD
> licence ?
>
> What a bad news for the community ... ! :o(
>
> PG-R seems to be the best integrated solution of the moment ... Still a lot
> of work ... but Darren and others are making a real good job !
>
> DBMirror or rserv (commercial application) seems to be only triggers, and
> little demon not included in PostgreSQL system ... as PG-R is ...
>
> PostgreSQL really need an official Replication solution to be definitively
> secured in a productive environnement ... and I think I'm not the only one
> thinking like that ... looking the survey of Postgres.org web site :
> http://www.postgresql.org/survey.php?View=1&SurveyID=9
> --
> Herv? Piedvache
>
> Elma Ing?nierie Informatique
> 6 rue du Faubourg Saint-Honor?
> F-75008 - Paris - France
> Tel. 33-144949901
> fax. 33-144949902
>

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