[pgpool-general: 2267] Re: PGPool and backend CPU usage

[Tatsuo Ishii]

How do you set up pgpool replication? Are you using streaming
replication of PostgreSQL?
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese: http://www.sraoss.co.jp

> Hi all,
> 
> We're  facing a situation that would like some expertise to be solved.
> 
> First of all, our setup consists of 3 databases Postgres 9.1, PGPool 3.2 STABLE checked out from the repository (rev 6dde744) and PGPoolAdmin 3.2.0.
> We have setup replication and load balancing, along with scripts for online recovery.
> The cluster works fine in terms of replicating and load balancing data.
> 
> But, the servers host other applications expect of the databases.
> Some applications require a lot of CPU when running.
> We found recently that when CPU is high in a backend, PGPool fails to update the data on this server and that causes a 'kind mismatch among backends' situation.
> 
> I know that there is a replication_stop_on_mismatch parameter in pgpool conf, but that will disconnect the database from the cluster and we will have to re-attach it (this could happen several times).
> 
> So I was wondering, if there is a more permanent workaround for this.
> Is it something we can configure in PGPool?
> Are there any minimum memory requirements that we could set to avoid this problem?
> Would that be in Postgres?
> Maybe the best option is to dedicate the server to run the database only (?).
> 
> Thanks in advance for your help and your time.
> 
> Regards,
> Stelios