[Pgpool-general] PgPool install, Part Deux

[Tatsuo Ishii]

> Hi, Marc!
> 
> 2009/7/7 Marc G. Fournier <scrappy at hub.org>
> 
> > Last time I tried, something got "out of sync", ended up breaking the
> > cluster and going to one DB until I had time to dive better into it, with
> > two brand new servers ... so, I'm going to make attempt two at this ...
> >
> 
> Be sure that both your nodes are a "hard copy" one of the other.
> For example, use tar+gzip+cp or rsync in order to copy the whole pg-cluster
> from one node to another.
> 
> First, I take it 8.4.0 as a backend isn't a problem?  I can use 8.3 if I
> > have to ...
> 
> 
> I dont know about it.. Any tests with 8.4 would be welcome..

I did a small try with 8.4 and saw no problem except that pgpool does
not understand WITH clause is variant of SELECT and does not do load
balancing. (I'm sloly working on updating pgpool-II parser to adapt
8.4).

> > load_balance_mode?
> 
> 
> >From the docs:
> load_balance_mode:
> When set to true, SELECT queries will be distributed to each backend for
> load balance. Default is false.
> 
> So, if you want to load balance your selects do use it! :)
> 
> 
> > replication_stop_on_mismatch?
> 
> 
> >From the docs:
> replication_stop_on_mismatch:
> When set to true, pgpool-II degenerates the backends and keeps the service
> only with the Master DB if data mismatch occurs. If false, pgpool-II just
> terminates the query. Default is false.
> 
> AFAIU, we could say that if this option is enabled, then in case that pgpool
> finds data mismatch between nodes, it will degenerate 'not master nodes', in
> other words, it deactivates replication. It could be interesting for
> production enviroments..
> 
> 
> > Any other recommendations?
> 
> 
> Read the doc again :)
> http://pgpool.projects.postgresql.org/pgpool-II/doc/pgpool-en.html
> 
> Whish you good luck!
> J. Carlos Muro