[Pgpool-general] Load balance diff betweeb PGPOOL I and II

[Tatsuo Ishii]

> Im just testing loading balance between 2 postgresql servers.
> 
> I could see that pgpool I treats loading balance diferent then pgpool 2.
> 
> When im in replication mode and load balance mode in pgpool 2 , queries are not loading balance.
> 
> An simple example:
> i connected to pool and do the following query several times.
> select datname from pg_database;
> 
> in the 2 nodes i have differents databases:
> one node i had 3 databases and the other one i have 4.... just to test the load balancing, returing me the
> differents databases names....
> 
>  The pool always returned me the first one database, in that case the 3 databases names ...
> 
> when im using pgpool version 1, i connected to the pool and did the same query and
> when i did the same querie i get the differents databases names. sometimes the 3 databases sometimes the 4
> ones... as i see the querie is always load balancing.

Yes, pgpool-I does load balance at each query. While pgpool-II does
load balance at each session.

> i tried to disconnected from the pool and connect again, but i get the same situation, it seems that the
> query is just sent to the first one database in my pgpool.conf

Try more. Eventually the connection will be forced to the second
DB. Or... you start an explicit transaction? In this case load balance
always directs to the first node. See doc/load_balance.png for more
details.
--
Tatsuo Ishii
SRA OSS, Inc. Japan